by James X. Xiong, Ph.D., CFA; Thomas Idzorek, CFA; and Peng Chen, Ph.D., CFA
Please click here for Appendixes
Executive Summary
- This article explores a variety of asset allocation issues associated with deferred variable annuities with guaranteed minimum withdrawal benefits for life (VA+GMWB) to develop a framework for optimal retirement portfolios.
- We begin by analyzing the value of the guarantee (GMWB) and its role in the portfolio context. It will lower the net return of the VA account; however, it provides a hedge against market downside risk, and if the investor holds the contract for the rest of his or her life, the VA+GMWB should provide him or her with an income stream for life.
- We present an optimization framework for making this very important tradeoff that considers the investor's unique financial situation as well as his or her specific preferences. Over the long term, the VA+GMWB return distribution is expected to be more conservative than the VA alone, which adds complexity to the determination of an optimal product mix.
- In the spirit of Sharpe's method for estimating the "effective mix" of a mutual fund, we develop a method for estimating the effective mix of a VA+GMWB.
- This study centers on a Monte Carlo simulation-based optimization to find an optimal product type mix by maximizing a utility function at the life expectancy.
- All other things being equal, the study finds (1) The higher the risk tolerance, the lower the VA+GMWB allocation; (2) The higher the age, the lower the VA+GMWB allocation; (3) The higher the subjective life expectancy, the higher the VA+GMWB allocation; (4) The higher the ratio between wealth and income gap, the lower the VA+GMWB allocation; and (5) The preference for bequest has almost no effect on the VA+GMWB allocation.
James X. Xiong, Ph.D., CFA, is a senior research consultant at Ibbotson Associates, a registered investment adviser and wholly owned subsidiary of Morningstar Inc.
Thomas Idzorek, CFA, is chief investment officer and director of research for Ibbotson Associates.
Peng Chen, Ph.D., CFA, is president of Ibbotson Associates.
Investors are living longer than ever before; yet, there has never been more uncertainty regarding the future of what have traditionally been regarded as guaranteed sources of income, such as traditional defined-benefit pension plans and Social Security. Traditional defined-benefit pension plans and Social Security both offer the investor what is thought of as a guaranteed income stream for life during retirement. The switch from defined-benefit pensions to defined-contribution plans that has taken place in corporate America switches the responsibility of providing a lifetime income stream from employers to individuals. As a result, many retirees face two related risks that threaten their financial well-being in retirement:
- Longevity risk—the risk of outliving one's savings and facing financial ruin
- Investment performance risk—the risk that bad investment performance will reduce the value of the investor's portfolio
Tools for controlling these risks should be of particular
interest to retirees. A large number of innovations have taken
place in the development of insurance products that enable today's
retirees to help mitigate these two risks and build a more secure
retirement. Unfortunately, these insurance features can be
difficult to understand, and discerning how and when such features
might be expected to help them can be quite confusing to
retirees.
The average 65-year-old retiree can expect to live about another 20
years. Some retirees won't live past 70, while record numbers are
expected to live past the century mark. This creates considerable
uncertainty on the issue of how much money will be needed to fund
retirement. Once in retirement, a portfolio of traditional assets
and the size of a prudent sustainable retirement income stream that
it can support are very sensitive to market fluctuations. A series
of ill-timed downturns in the market could drastically increase the
longevity risk faced by investors, forcing them to dramatically
decrease their retirement standard of living. In the absence of
cash flows, the sequence of returns is not important. In
retirement, outgoing cash flows make the sequence of returns very
important.
The fear of outliving one's assets drives some investors to adopt
unnecessarily frugal lifestyles, while at the other end of the
spectrum, some investors will spend too much depleting their
savings early in their retirement years. Most investors can avoid
these extreme outcomes through a proper combination of traditional
investment products, such as mutual funds or exchange-traded funds
(ETFs), and insurance products that offer a guaranteed income
stream for life, such as payout annuities or variable annuities
with lifetime living benefit guarantees. A type of insurance known
as longevity insurance can ensure an income for life no matter how
long the retiree lives.
The first widely available form of longevity insurance that helped
investors control the risk of outliving their savings was payout
annuities (immediate annuities). With payout annuities, an investor
purchases an annuity contract with a lump sum payment and in return
the insurance company promises to pay the investor an income stream
for as long as he or she lives. Concerns around exchanging a large
amount of one's net worth for a contract coupled with fears of an
early death prevent some investors from purchasing payout
annuities.
A new type of longevity insurance has emerged that is purchased for
ongoing insurance fees and does not require the annuitization of
the investor's assets. Like the longevity insurance offered from
payout annuities, this new form of longevity insurance, called a
guaranteed minimum withdrawal benefit (GMWB) for life, can also
guarantee an investor an income stream for life, provided that the
conditions of the longevity insurance agreement are met.
Relatively little work has been done on how best to combine
traditional investments with insurance products that offer a
guaranteed income stream for life to create a retirement income
solution that properly mitigates the primary risks faced by
retirees: longevity risk and investment performance risk. The
seminal work on finding the optimal mix including immediate payout
annuities was Chen and Milevsky (2003). In this article, we expand
and refine their model to determine the optimal split between
traditional investments and variable annuities with guaranteed
minimum withdrawal benefits for life (VA+GMWB).1
We believe the easiest way to incorporate this into the traditional
investment process is to follow the typical strategic asset
allocation decision with a secondary product type optimization that
determines the high level allocation to traditional products and
insurance products. The optimization will simultaneously solve for
(1) the optimal percentage to invest in traditional products, (2)
the optimal percentage to invest in the VA+GMWB, and (3) the
detailed asset allocation model for the percentage allocated to
traditional products.
We begin this analysis with an overview of the mechanics of the
VA+GMWB and a procedure for estimating the value of the common
features associated with the rider. In this case, the "VA" refers
to a deferred variable annuity insurance contract chassis. Ignoring
the potential preferred tax treatment of the deferred variable
annuity legal structure, conceptually the deferred variable annuity
is similar to a mutual fund.2 For an additional fee, the
GMWB insurance rider can be added to the base insurance contract.
The GMWB alters the behavior of a portfolio making the effective
asset allocation more conservative. We present a Monte Carlo
simulation framework for estimating the effective asset allocation
of a VA+GMWB. Finally, we present the intuition behind our
guaranteed income allocator optimization framework for determining
the product type split, although the mathematical details are saved
for Appendix D. (All appendixes to this article are available on
the Journal Web site in conjunction with the electronic
version of this article, and FPA member login may be required.)
Overview of VA with Lifetime GMWB
A recent innovation in deferred variable annuity products is the
guaranteed minimum withdrawal benefit (GMWB) rider. The GMWB is
often referred to as a benefit rider. We will focus on the GMWB
rider for life in this study, which is sometimes referred to as a
guaranteed lifetime withdrawal benefit or GLWB. The GMWB rider for
life gives investors the ability to protect their retirement
investments against downside market risk by allowing the investor
the right to withdraw a fixed percentage of the benefit base each
year until death. At the time of writing, typical lifetime GMWB
products offer a fixed percentage of the benefit base or guaranteed
withdrawal rate of approximately 5 percent at age 65, even though
the GMWB fee may vary for different products or companies. The
guaranteed incomes continue even if the linked deferred VA account
value drops to zero. The benefit base, sometimes referred to as the
protected base, can step up and resets to the high-water mark of
the contract value on the rider anniversary date when the market
has performed well. The remaining contract value at death will be
paid to beneficiaries, which removes the investor concern about
giving up liquidity to the heirs (that is, if I die early, my whole
family loses).
Figure 1 plots the guaranteed income assuming that one bought a
hypothetical VA+GMWB contract at the end of year 1978 for $50,000.
The inflation-adjusted equivalent is also plotted for comparison
purpose. The VA asset allocation remains 80 percent stocks/20
percent bonds for the entire period from 1979 to 2008. All fees are
at the appropriate average level shown in Appendix C. The
guaranteed income steps up whenever the contract value exceeds the
current benefits base and never decreases, and reaches $190,793 by
2008. The first payment of $50,000 starts at the beginning of 1979.
The stock market crash in year 2000 and the market crisis in 2008
do not reduce the income, and the guarantee keeps the income level
flat. It is worth noting that over this period, the
inflation-adjusted equivalent to $50,000 in 1979 is $154,529 in
2008; thus, the annual income kept up with inflation.

The corresponding contract values and benefit bases from 1979 to
2008 are shown in Figure 2. Because of strong market performance
from 1979 to 1999, the benefit base steps up in a number of the
years. The dynamics of the VA+GMWB contract value is documented in
Appendix A.

Figure 2 illustrates a couple of important points about the
VA+GMWB. First, in a predominantly rising market (for example, 1979
to 2000) the difference between the contract value and the benefit
base is relatively small. Conversely, in a predominantly falling
market (for example, 2000 to 2008) the difference between the
contract value and the benefit base is significant. Under such
conditions, selling the contract would result in a substantial loss
of future income. To realize the benefit of this type of longevity
insurance, the investor must approach the VA+GMWB as an investment
for life.
The Value of a Lifetime GMWB
Before we can allocate assets into the VA+GMWB products, we need
to understand the value of a lifetime GMWB. The value of a lifetime
GMWB is directly linked to its fee. Bauer, Kling, and Russ (2008)
establish a universal pricing framework for such guaranteed
benefits. Holz, Kling, and Russ (2007) apply the Bauer, Kling, and
Russ (2008) framework to price the lifetime GMWB using a Monte
Carlo simulation technique. In this paper, we follow Holz, Kling,
and Russ (2007) to calculate the value of lifetime GMWB riders for
different parameters using the deterministic withdrawal method; the
details are documented in Appendix B. The deterministic withdrawal
is the maximum withdrawal allowable for the lifetime GMWB contract,
for example, 5 percent of the benefits base. Appendix C contains
the asset allocation models, capital market assumptions, and fee
structures used in the simulations.
The relevant parameters that affect the value of a lifetime GMWB
include the volatility of the VA account portfolio, the age of the
investor or life expectancy, the maximum allowable withdrawal rate,
and the frequency of the benefits base step-up.
In this paper, we only consider the deterministic withdrawal method
from a less sophisticated investor's perspective, not from an
arbitrageur's perspective, for two reasons. First, the surrender
charge associated with the lifetime GMWB will deter investors from
surrendering the rider during a surrender period. Second, Holz,
Kling, and Russ (2007) show that the value of a lifetime GMWB is
only slightly higher to an arbitrageur with optimal behavior than
it is to the more simplistic deterministic withdrawal behavior of a
typical investor.
Figure 3 shows the relationship between the volatility of the VA
asset allocation and the value of lifetime GMWB. In Figure 3, the
risk-free rate is assumed to be 4 percent with an annual step-up
feature. Standard option pricing theory states that the higher the
volatility, the higher the option price. The same conclusion holds
true for the lifetime GMWB. Should insurance companies charge a
fixed fee for the GMWB, no matter the risk of the portfolio (the
current common practice), investors should select an aggressive
asset allocation for the VA+GMWB.

The estimated fair value of lifetime GMWB for an aggressive VA
asset allocation (80 percent equities) is about 0.8 percent.
Currently, the typical GMWB rider fee ranges from 0.6 percent to
0.9 percent, regardless of the asset allocation. Those with a
conservative VA+GMWB asset allocation are probably overpaying, and
those with an aggressive VA+GMWB asset allocation are probably
getting a fairly good deal.
Holz, Kling, and Russ (2007) show that the price for a lifetime
GMWB is higher for younger investors, all else the same. This
result flows directly from option pricing theory; when the time (T)
to expiration is long, the value of an equivalent option is higher.
Holding all of the other parameters constant and assuming no
step-up, the paper also shows that the price is higher with a
higher maximum allowable withdrawal rate. This is intuitive, as a
higher income stream has a higher present value than a lower income
stream.
In a typical new VA+GMWB contract, however, the maximum allowable
withdrawal rate increases with the buyer's age, for example, 5
percent at age 65, 5.5 percent at age 70, and 6 percent at age 75,
based on our surveys. Figure 4 shows the age and maximum withdrawal
rate effect on the value of lifetime GMWB from our Monte Carlo
simulation results. We assume that the contract has an annual
step-up feature, the VA asset allocation is 80/20, and the
risk-free rate is 4 percent. It can be seen that even with a higher
withdrawal rate of 6 percent at age 75, the lifetime GMWB value is
still slightly less than that for the 5 percent withdrawal rate at
age 65.3 The value of a lifetime GMWB purchased at age
70 with 5.5 percent withdrawal rate falls between the lifetime GMWB
purchased at age 65 with 5 percent withdrawal rate and the lifetime
GMWB purchased at age 75 with 6 percent withdrawal rate.

Figure 5 shows the step-up frequency impact on the value of
lifetime GMWB. The frequency ranges from daily, weekly, monthly, to
quarterly step-up (four times a year), to annual step-up (once a
year), and to no step-up (zero times a year). It shows that the
most frequent step-up feature has the highest value, all else the
same. While a quarterly step-up is often trumpeted as wonderful
improvement over an annual step-up, we estimate the incremental
fair value to be 12 basis points. The incremental fair value is
about 15 basis points when the step-up frequency is changed from
quarterly to daily. There is no significant difference among daily,
weekly, and monthly step-ups.

In summary, the longer the life expectancy, the higher the expected
value of a lifetime GMWB. The more aggressive the VA+GMWB asset
allocation, the higher the value. The more frequent the benefits
base steps-up, the higher the value. The higher the maximum
withdrawal rate, the higher the value.
Later, when we present our framework for determining the optimal
product type mix, we will focus on what we call the "all-in" fee,
which includes all fees for the VA+GMWB. When shopping for a
VA+GMWB investors should strive to find a VA+GMWB combination in
which the standalone VA fees are comparable to the mutual fund fees
and GMWB fees are close to those presented in Figure 3, 4, and
5.
Effective Asset Allocation for VA+GMWB
In general, the deferred variable annuity account is invested in
certain pre-defined underlying funds, and its account value rides
up or down with the financial market. The list of available
investment strategies may be limited if the investor seeks to
attach the GMWB rider to the deferred VA contract. Nevertheless,
the investment strategies are subject to downside risk. The
lifetime GMWB acts as a form of portfolio insurance, protecting the
investor from downside risk. Conceptually, this is similar to a put
option that provides downside protection to a traditional
portfolio. Options change the characteristics of the expected
return distribution. That naturally gives rise to a critical
question: Does a lifetime GMWB enable a retiree to tolerate more
equity risk for other assets?
On one side, the rider fee will lower the net return of the VA
account, on the other side, the rider will provide a hedge against
downside risk. Therefore, over the long-term horizon, the VA+GMWB
return distribution is expected to be more conservative than the VA
alone.
We estimate the effective asset allocation for VA+GMWB through
Monte Carlo simulations. It turns out that the effective asset
allocation is dependent on the time horizon. At each period t, we
calculate the value of the total benefits of the VA+GMWB at both
the 50th percentile and the 5th percentile.
The value of the total benefits includes the total withdrawals and
the ending account value. The total withdrawals are the summation
of each guaranteed income payment, which is then compounded to
period t at the risk-free rate. The 50th and the
5th percentiles were selected because they capture the
relevant characteristics of the option feature of VA+GMWB.
We repeat the same Monte Carlo simulation procedures for a series
of traditional mutual fund portfolios with different asset
allocations. In each case, the income for each period is based on
the income of the VA+GMWB. To determine the effective asset
allocation of the VA+GMWB, we then minimize the distance of the
total benefits values at both the 50th percentile and
5th percentile between the VA+GMWB and a mutual fund
portfolio. The mutual fund asset allocation that minimizes this
distribution-based distance for each year is shown in Figure 6.

Figure 6 illustrates that the effective asset allocation for a
VA+GMWB with an asset allocation of 80 percent equities and 20
percent bonds depends on the time horizon. The maximum allowable
withdrawal rate is 5 percent. For a time horizon shorter than 10
years, the effective asset allocation remains unchanged at 80/20,
but for a longer time horizon (> 20 years), effective asset
allocation becomes more conservative at 40/60. As we will see
shortly, the effective asset allocation over the life expectancy
(about 20 years) is useful in determining both the optimal product
allocation (VA+GMWB vs. traditional products) and the optimal asset
allocation inside the traditional assets.

One quick example should provide additional insight. Suppose that
the time horizon is 30 years, the target overall strategic asset
allocation is 50 percent equities and 50 percent bonds, and the
investor has $1 million to invest. For now, we assume that 20
percent of the total asset will be invested in a VA+GMWB with asset
allocation of 80 percent equities and 20 percent bonds. If the
impact of the embedded guarantee or option is ignored, the
traditional assets will need to have an asset allocation of 43
percent equities and 57 percent bonds so that the total weighted
average asset allocation is 50 percent stocks and 50 percent bonds.
Now, considering that the effective asset allocation of VA+GMWB is
estimated at a far more conservative 40 percent equities and 60
percent bonds at a 30-year horizon, however, the traditional assets
need to have an asset allocation of 53 percent equities and 47
percent bonds to create a portfolio that behaves most like the
target overall strategic asset allocation of 50 percent equities
and 50 percent bonds.
Determining the Optimal Mix
The details of our guaranteed income allocator optimization framework for determining the product-type split are presented in Appendix D. The primary factors that drive our model for determining the optimal proportion of an investor's target asset allocation that should be implemented with traditional products and variable annuities with guaranteed minimum withdrawal benefits for life are described below.
- Risk Tolerance—The investor risk tolerance is an input for the model and can be determined in a variety of ways. Conservative investors prefer certainty to uncertainty, and therefore, prefer products that offer downside protection and guaranteed income. Conversely, aggressive investors are not as concerned about downside protection and guaranteed income.
- Wealth vs. Total Retirement Expenses—Investors who have large amounts of wealth relative to their total expected retirement expenses have little to no need for longevity insurance and their portfolios can withstand sustained market downturns and longevity risk without threatening their living standards.
- Existing Sources of Guaranteed Income vs. Annual Income Need—Investors need to compare the amount of annual income they will receive from a traditional defined benefit pension, Social Security, and existing investments that offer a guaranteed income stream for life to their annual income need. If the existing sources of guaranteed income will cover a substantial part of the annual income need, there is a lower need for additional longevity risk and investment performance risk insurance.4
- Subjective Life Expectancy—The longer an investor lives, the greater the longevity risk and the need for longevity insurance. On average, healthy individuals with healthy lifestyles and relatives who tend to live longer than normal are more likely to benefit from variable annuity products with GMWB features.5
- Fees vs. Insurance Benefits—The structure and fees of different insurance products vary widely. Prior to investing, it is important to understand the potential insurance benefits and costs. Because similar benefits may be available in multiple products or combinations of products, it is important to compare other alternatives.
- Likelihood of Meeting the Contract Conditions—Investors who are likely to liquidate all or part of the contract value are less likely to benefit from the GMWB for life insurance rider. This includes investors who move from investment to investment and investors who lack the discipline to only withdraw the guaranteed amount.
- Desire to Leave a Bequest vs. the Desire for Lifetime Income—For most investors, the desire to leave the maximum possible bequest to their heirs is unusual. Most investors treat a bequest as a secondary concern that ranks below the desire for a lifetime of income. Investors with unusually high bequest motives will more likely benefit from investing in traditional assets.
- Investment Options—For most investors, this is not an issue because there are typically a large number of acceptable underlying investment options. In extraordinary circumstances, there may not be an acceptable underlying investment for a particular individual.
Most of these factors can be determined by using a specialized
retirement income-oriented asset allocation questionnaire. In
addition to these factors, we assume the target overall strategic
asset allocation has already been determined.
These factors drive a Monte Carlo simulation-based optimization
that determines the product type split to maximize the investor's
utility at the life expectancy. The optimization simultaneously
solves for (1) the optimal percentage to invest in traditional
products, (2) the optimal percentage to invest in the VA+GMWB, and
(3) the detailed asset allocation model for the percentage
allocated to traditional products. For now, we proceed with a
large-scale scenario test to illustrate the intuition of the
model.
Scenario Studies—A Large-Scale Test
To help illustrate the effect of the different factors on the
optimal product type split, we programmatically ran a large number
of cases or scenarios to observe a large number of permutations
spanning the applicable space. This included 675 different
permutations on different parameters such as age, risk aversion,
subjective life expectancy, and preference for bequest.
In this paper, we do not limit the amount that can be allocated to
the VA+GMWB. In practice, however, we put a maximum on the amount
that can be allocated to the VA+GMWB to avoid what one might deem
to be too much product-specific risk. The main reason is that we
believe there is a strong likelihood that the VA+GMWB will be
implemented with a single product. There is no reason to think that
such products will have an issue, but the guarantees in such cases
depend on the creditworthiness of the issuer, and the nature of the
guarantees is that they are most likely to pay off over a
relatively long time horizon during a market crisis. For example,
the credit crunch of 2007 highlighted the potential danger of some
money market funds—a type of investment that many
investors would have deemed very safe and used as a potential
resting spot for 100 percent of their wealth. A basic and prudent
strategy is to diversify across asset classes and across products.
We want to avoid having a single product that could be exposed to
particular unforeseen crisis dominate an individual's
portfolio.
Because of the way VA+GMWBs are currently priced, we assume that
the asset allocation of the VA+GMWB is fixed at 80/20 for all the
scenarios and that the overall target strategic asset allocation
for all assets is known.6 Appendix D shows that our
objective function maximizes the utility at the life expectancy
(for example, a 20-year horizon). We have shown that the effective
asset allocation for the VA+GMWB is 40/60 for the 20-year horizon.
Therefore, the following relationship holds:
S = P x 40% + (1 – P) x T
where S is the known equity portion in the strategic asset
allocation, for example, 50 percent. P is the unknown product
allocation to VA+GMWB and T is the unknown equity allocation to the
traditional asset, respectively. P and T are related to each other
by the completion portfolio and both of them can be solved
simultaneously by maximizing the utility function shown in Appendix
D.
Overall, the following relationships were observed after the 675
cases were optimized:
• The higher the risk tolerance, the lower the VA+GMWB
allocation
• The higher the age, the lower the VA+GMWB
allocation
• The higher the subjective life expectancy, the higher
the VA+GMWB allocation
• The higher the ratio between wealth and income gap,
the lower the VA+GMWB allocation
• The preference for bequest has almost no impact on the
VA+GMWB allocation
Risk Tolerance and Age
Figure 7 illustrates the effect of two factors: age and risk
tolerance, where age is closely tied to the individual's objective
life expectancy. All else equal, conservative investors receive
higher allocations to the VA+GMWB than aggressive investors, and
younger investors receive higher allocations to the VA+GMWB than
older investors. The effect of age is consistent with the value of
the GMWB on age determined earlier (see Figure 4). Again, we see
that the longevity insurance from a VA+GMWB is closely related to a
put option or portfolio insurance. The value of an option increases
with time; thus, for younger investors there is more time for the
"put option" of the VA+GMWB to be "in the money."
Note that the withdrawal rates in Figure 7 of 5 percent, 5.5
percent, and 6 percent correspond to ages 65, 70, and 75,
respectively, as shown in Figure 2. These withdrawal rates are
current approximate industrial average rates. Higher withdrawal
rate assumptions lead to higher estimated VA+GMWB values, thus
higher VA+GMWB allocations, holding all other parameters
constant.
Economic Situation
Figure 8 illustrates the effect of the ratio of wealth divided by the annual funding gap (annual income need less existing sources of guaranteed income). This ratio captures information about the individual's wealth vs. total retirement expenses and existing sources of guaranteed income vs. annual income need, and serves as a collective measure of the individual's economic situation. Wealthy or well-funded investors do not face longevity risk; thus, the need for longevity insurance diminishes as the investor's funding status improves. Intuitively, as the possibility of running out of money declines, so does the allocation to a VA+GMWB.

Subjective Life Expectancy
Based on an individual's age and current mortality tables, we can determine the objective life expectancy of an individual. However, individuals have more detailed knowledge of their unique family histories, lifestyle, and general health. These factors should enable them to make a qualitative assessment of whether they will live longer or shorter than average (as determined by the objective life expectancy estimate). Figure 9 illustrates the effect of the investor's assessment of his or her subjective life expectancy on the allocations to VA+GMWB for life. Intuitively, those who think they will live longer than the objective life expectancy face greater longevity risk and consequently need more longevity insurance; thus, all else equal, they receive a larger allocation to the VA+GMWB product type.

Preference for Income vs. Preference for Bequest
The final factor that we analyzed during this large-scale test was the effect of the individual's preference for lifetime income (personal consumption) vs. his or her preference to leave the largest possible bequest. In contrast with the Chen and Milevsky (2003) framework based on immediate payout annuities in which the bequest preference is very important, this factor has almost no effect on the amount that is allocated to the VA+GMWB product type. This is not surprising, as the remaining VA+GMWB contract value is paid to the investor's beneficiary or beneficiaries on death, which is fundamentally different from the immediate payout annuity products, in which this type of factor has a substantial effect on the amount allocated to insurance products.
Conclusions
In summary, as life expectancy increases, more and more retirees
will live into their late 80s and beyond. Future market performance
is uncertain and exposes investors to investment performance risk.
Poor market performance dramatically increases longevity risk
associated with increasing life expectancy, but the degree to which
retirees face longevity risk depends on a large number of factors,
including: wealth, Social Security, defined-benefit pensions,
retirement expenses/lifestyle, how long they live, and uncertain
market performance. These factors coupled with individual
preferences should be considered when determining the role of
variable annuities with guaranteed minimum withdrawal benefits in a
portfolio.
We have studied the characteristics of the VA+GMWB for life and
built a framework to determine the optimal mix between traditional
assets and VA+GMWB for a retirement portfolio. The major findings
are:
• The higher the risk tolerance, the lower the VA+GMWB
allocation
• The higher the age, the lower the VA+GMWB
allocation
• The higher the subjective life expectancy, the higher
the VA+GMWB allocation
• The higher the ratio between wealth and income gap,
the lower the VA+GMWB allocation
• The preference for bequest has almost no effect on the
VA+GMWB allocation
Hedging longevity risk is crucial. Implementing a target asset
allocation with a mixture of traditional investment products and
variable annuities with guaranteed minimum withdrawal benefits for
life creates a powerful retirement income solution that enables
investors to participate in the potential upside of good markets
and provides them with income for life in bad markets.
Endnotes
- We use a utility maximization framework to determine the optimal split as shown in Appendix D.
- Additional features are sometimes included as part of the base variable annuity contract, and the investor can periodically switch among different approved investment vehicles (for example, risk-based asset allocation portfolios or combinations of different sub-accounts) without selling the contract.
- It is easy to see how such a framework could be used to design an online calculator that would help investors time the purchase of the GMWB.
- Wealth vs. total retirement expenses and existing sources of guaranteed income vs. annual income need are measures of the individual's economic situation. We typically find it helpful to combine these two factors and focus on the ratio of wealth divided by the annual funding gap (annual income need less existing sources of guaranteed income).
- "Objective" life expectancy refers to the actuarial life expectancy. "Subjective" life expectancy is based on the individual's knowledge of his or her current health status, lifestyle, and family health history.
- When selecting a VA+GMWB, most insurance companies allow investors to select from a series of asset allocation model portfolios that vary from conservative to moderately aggressive, or from a list of sub-accounts. However, in almost all cases, the insurance company limits the aggressiveness of the portfolio by allowing a maximum equity exposure of 80 percent.
References
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Holz, Daniel, Alexander Kling, and Jochen Russ. 2007. "GMWB for
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