THE LONG-RANGE DISABILITY ASSUMPTIONS

FOR THE 2024 TRUSTEES REPORT

OFFICE OF THE CHIEF ACTUARY

SOCIAL SECURITY ADMINISTRATION

May 6, 2024
Disability, Page 2 

DISABILITY

ASSUMPTIONS FOR THE 2024 TRUSTEES REPORT

OFFICE OF THE CHIEF ACTUARY, SSA

TABLE OF CONTENTS PAGE

1 OVERVIEW ................................................................................................................................... 3

2 DISABILITY INCIDENCE RATE ..................................................................................................... 5

2.1 EFFECTS OF ECONOMIC CYCLES AND POLICY CHANGES ON DI INCIDENCE RATES .................................................. 5

2.2 ASSUMED FUTURE DISABILITY INCIDENCE RATES ................................................................................................... 6

3 DISABILITY DEATH RATE ............................................................................................................ 8

4 DISABILITY RECOVERY RATE ..................................................................................................... 8

5 DISABILITY PREVALENCE RATES ............................................................................................... 9

CHART 1: EFFECT OF THE ECONOMY ON THE DI INCIDENCE RATE...............................................................................11

CHART 2: NEW DISABLED-WORKER AWARDS PER 1,000 EXPOSED (INCIDENCE RATE) ...............................................12

CHART 3: MALE DISABLED-WORKER AWARDS PER 1,000 EXPOSED (INCIDENCE RATE) BY AGE GROUP....................13

CHART 4: FEMALE DISABLED-WORKER AWARDS PER 1,000 EXPOSED (INCIDENCE RATE) BY AGE GROUP ................14

CHART 5: AGE-SEX-ADJUSTED COMPARISON OF SSA GENERAL POPULATION MORTALITY TO DISABLED WORKER 

MORTALITY ..........................................................................................................................................................15

CHART 6: DISABLED-WORKER RECOVERIES PER 1,000 BENEFICIARIES.......................................................................16

CHART 7: DISABLED-WORKER PREVALENCE RATES THROUGH NRA (PER 1,000 INSURED POPULATION) ...................17
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1 Overview

Each year the Board of Trustees of the Federal Old-Age and Survivors Insurance (OASI) and 

Disability Insurance (DI) Trust Funds provides an annual report to the Congress on the financial 

and actuarial status of the Old-Age, Survivors, and Disability Insurance (OASDI) program. The 

Office of the Chief Actuary (OCACT) produces projections of future cost and income based on 

three separate sets of long-range (75-year) assumptions for three key disability variables. The 

intermediate (alternative II) set of assumptions represents the Trustees’ best estimate for future 

experience, while the low cost (alternative I) and high cost (alternative III) sets of assumptions 

are more and less favorable, respectively, from the perspective of program cost as a percent of 

taxable payroll. In addition, the intermediate assumptions serve as the point of comparison for 

sensitivity analysis and the central tendency for the stochastic projections presented in the 

OASDI annual report to the Board of Trustees (the “Trustees Report”). This memorandum 

presents the long-range disability assumptions used in the 2024 Trustees Report. 

At this time, there is no consensus on what the lasting effects of the COVID-19 pandemic on 

long-term disability trends will be. The Trustees continue to assume that the pandemic will have 

no significant net effect on most individual long-range ultimate assumptions. 

The key disability assumptions are: 

• The disability incidence rates by age group and sex, 

• The disability death rate improvement factors by age group and sex, and 

• The disability recovery rates by age group and sex. 

The ultimate disability incidence rate assumptions for the 2024 Trustees Report are lower for all 

alternatives than those assumed for the 2023 Trustees Report. The alternative II age-sexadjusted ultimate disability incidence rate was lowered from 4.8 awards per thousand exposed in 

the 2023 Trustees Report to 4.5 per thousand in the 2024 Trustees Report. Incidence rates have 

generally declined since the peak in 2010. Application and incidence rates are both near historic 

low levels. The lower ultimate disability incidence rates assumed for the 2024 Trustees Report 

are an incremental decrease from the rates previously assumed, in order to reflect a portion of the 

recent very low levels experienced, and the expectation that many of the factors contributing to 

the recent declines will persist.

Our methodology for projecting disability death rates has not changed for the 2024 Trustees 

Report. The disability death rates for the 2024 Trustees Report are dependent on general 

population mortality and actual 2023 disabled worker death experience. 

The ultimate disability recovery rate assumptions are higher for all alternatives than those used 

for the 2023 Trustees Report. The alternative II age-sex-adjusted ultimate disability recovery 

rate was increased from 10.4 per thousand in the 2023 Trustees Report to 10.8 in the 2024 

Trustees Report to capture slightly higher recovery experience since 2005. 

There are no significant method changes in the disability model for the 2024 Trustees Report. 
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The historical changes in incidence and recovery rates have led to disability prevalence rates for 

men reaching their lowest level since 1989. Prevalence rates for women are at a similarly low 

level. The age-sex-adjusted prevalence rate is currently below 33 per thousand insured and is 

projected to rise to over 40 per thousand by the end of the long-range projection period. 

Factors contributing to the recent declines in disability applications, awards, incidence, and 

prevalence include the changing nature of work, resulting in part from the shrinking share of the 

population that is at traditional working ages, and the greater availability of health care because 

of the Affordable Care Act. The changing nature of work, which was accelerated by the 

pandemic, allows more people with significant impairments to continue employment. Many

companies have been expanding accommodations in recent years, giving workers more 

flexibility including the option to telework. 

The following table shows values for key summary measures for the disability assumptions. 1 

Key Disability Summary Measures for the Long-Range (75-year) Projection Period

2023 Trustees Report and 2024 Trustees Report

2023 Trustees Report 

Alternative

2024 Trustees Report 

Alternative

2024 Trustees Report 

Less 2023 Trustees 

Report 

I II III I II III I II III

Ultimate age-sex-adjusted disability 

incidence rate per 1,000 exposed

workers

3.8 4.8 5.8 3.6 4.5 5.4 -0.2 -0.3 -0.4

Age-sex-adjusted disability death rate 

per 1,000 beneficiaries for the last 

year of the 75-year projection

21.5 12.4 6.1 21.5 12.4 6.2 0.0 0.0 0.1

Ultimate age-sex-adjusted disability 

recovery rate per 1,000 beneficiaries

12.5 10.4 8.3 13.0 10.8 8.6 0.5 0.4 0.3

The disability incidence and recovery rates reach ultimate values for the tenth projection year 

and thereafter. During the first ten years of the projection period, the long-range model 

reconciles with projections from the short-range model. 

The lower ultimate disability incidence rate assumption by itself results in a 0.08 increase 

(improvement) in the long-range OASDI actuarial balance. Including recent disability data, the 

higher ultimate disability recovery rate assumption, the higher labor force participation rates 

expected because of the lower ultimate disability incidence rate assumption, and changes in nearterm disability assumptions increased (improved) the actuarial balance by an additional 0.04 

percent of payroll, for a combined total increase of 0.12 percent of payroll. 

The remainder of this memorandum provides details regarding the historical values and future 

values for each of the disability assumptions, and the basis for the assumptions. 

1

 The death rates shown are for the last year of the 75-year projection period. For the 2023 and 2024 Trustees 

Reports, the last years are 2097 and 2098, respectively. There is a small amount of mortality improvement reflected 

in the death rates between 2097 and 2098. 
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2 Disability Incidence Rate

2.1 Effects of Economic Cycles and Policy Changes on DI Incidence Rates 

Disability incidence rates are the proportion of workers in a given year, insured for but not 

receiving disabled-worker benefits (exposed population), who file for and are awarded disabledworker benefits. The age-sex-adjusted historical and short-range projected alternative II 

incidence rates are shown in Chart 1. A number of specific economic and policy drivers have 

influenced disability program cost historically and will continue to have an effect on disability 

incidence. Periodic economic recessions, as indicated by the civilian unemployment rate in red 

in Chart 1, have been associated with temporary increases in disability incidence. Incidence rates 

tend to increase temporarily in bad economic times. Some individuals who gradually develop 

conditions that would qualify for DI benefits based on the severity of their medicallydeterminable impairment are able to continue work at a level in excess of substantial gainful 

activity (SGA) given the opportunity and needed assistance during a period of strong economic 

activity and demand for workers. However, with elevated unemployment rates like those seen in 

the 2007-09 recession, many of these individuals will lose employment and will seek DI 

benefits. 

The recession that began in December 2007 resulted in an increase in disability applications and 

incidence to peak levels in 2010 that were exceeded only by the peak in 1975. One apparent 

exception to the relationship between disability incidence and economic recessions is the strong 

recession of 1981-82. The effect of that recession appears to have been offset by the net effects 

of the 1980 Amendments, which: (1) sharply increased the levels of pre-effectuation review of 

disability allowances and continuing disability reviews of current beneficiaries; (2) introduced 

the extended period of eligibility to encourage work; and (3) lowered the maximum family 

benefit for DI beneficiaries.

Additional policy changes over the years had significant effects on disability incidence. Doubledigit ad-hoc benefit increases in 1970 through 1974 made disability benefits more attractive. 

The 1984 Amendments may have offset the effects of a strong economic recovery with increased 

emphasis on multiple impairments and mental listings, and the requirement to show medical 

improvement for benefit cessation. The SSI outreach to disabled adults likely added to the 

effects of the 1990-91 recession. Also, the effects of a strong economic recovery from 1995 to 

2000 on lowering incidence rates may have been enhanced by the 1996 Amendments, which 

eliminated drug addiction and alcoholism as disabling conditions. 

Incidence rates have fallen steeply since 2010, concurrent with the recovery from the 2007-09 

recession. Incidence rates through 2023 have dropped to levels well below those expected over 

the long-term, and even below the levels that would be expected from the economic recovery 

alone. Contributing factors to the decline through 2019 in disability applications and awards 

include the changing nature of jobs in the economy, the improving economy indicated by the low 

unemployment rate, the greater availability of health care because of the Affordable Care Act, 

and increasing job flexibility and accommodation by many employers in an increasingly 

competitive labor market. Incidence rates declined to an extraordinarily low level in 2019, at the 

end of an extended period of economic recovery, resulting in the lowest disability prevalence 

rate for men since 2001, and a similarly low level for women. Incidence rates dropped even 
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further in 2020 and 2021, and to an all-time low in 2022, partly due to the effects of the COVID19 pandemic. Future policy changes, technological advancements, and economic cycles will 

undoubtedly continue to cause fluctuations in disability incidence rates. 

2.2 Assumed Future Disability Incidence Rates 

In the 2024 Trustees Report, incidence rates are projected to rise to a temporary peak level for 

2027 as some of the reduced levels of new benefit awards in recent years are expected to be 

realized in the next few years. After 2027, incidence rates generally decline from the peak, 

through the rest of the short-range period to the ultimate assumed level of incidence in 2033. In 

2033, at the end of the short-range period, age-sex-specific incidence rates are expected to 

approximate the ultimate rates. These ultimate age-sex-specific disability incidence rates were 

selected based on careful analysis of historical levels and patterns and expected future 

conditions, including the impact of scheduled increases in the normal retirement age. The 

ultimate incidence rates represent the expected average rates of incidence for the future.

For alternative II of the 2024 Trustees Report, the Trustees assume an ultimate age-sex-adjusted 

disabled-worker incidence rate of 4.5 per thousand exposed workers. This rate was 4.8 awards 

per thousand for the 2022 and 2023 Trustees Reports, 5.0 awards per thousand for the 2020 and 

2021 Trustees Reports, 5.2 awards per thousand for the 2019 Trustees Report, and 5.4 awards 

per thousand for the 2012 through 2018 Trustees Reports. The 4.5 per thousand ultimate 

incidence rate is 6 percent lower than the historical average experienced from 1995 through 2023 

(4.8 awards per thousand) and is 18 percent higher than the most recent ten-year historical 

average experienced from 2014 through 2023 (3.8 awards per thousand). With the assumed 

ultimate disability incidence rate above the average level over the last 10 years, the resulting 

projected disability prevalence rates will still rise to sustained levels through 2098 that are higher 

than recent historical rates. 

The ultimate incidence rates are calculated by age group and sex using a no-lag unemployment 

rate regression model for the years 1995-2019. The regression model uses data beginning in 

1995 to capture recent higher levels of female disability incidence rates. For ages 60-64, rates 

are increased from the regression results to reflect the planned increase in the Social Security 

Normal Retirement Age from 66 to 67. Rates for ages 65 and older are calculated using a 

weighted average of the base incidence rates and projected exposure. These rates are further 

adjusted with a 0.3 percent discount for the reinstatement of the reconsideration step of the 

disability appeals process and a 0.25 percent discount for the removal of the inability to 

communicate in English as an education category in the disability determination process. For the 

2024 Trustees Report, these rates, by age group and sex, were scaled down from the age-sexadjusted disability incidence rate of 4.8 per thousand assumed in the 2023 Trustees Report to the 

newly assumed age-sex-adjusted disability incidence rate of 4.5 per thousand. OCACT will 

continue to monitor experience closely and review the disability incidence assumption. 

The 2011 Technical Panel on Assumptions and Methods, appointed by the independent Social 

Security Advisory Board, suggested raising the 2011 Trustees Report ultimate alternative II 

incidence rate assumption of 5.2 to 5.8 per thousand. The 2015 Technical Panel agreed with the 

ultimate alternative II incidence rate assumption of 5.4 per thousand and suggested that OCACT

closely monitor experience. The 2019 Technical Panel suggested lowering the disability 
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incidence rate to 4.9 per thousand, consistent with the panel’s lower long-term unemployment 

rate assumption of 4.8 percent and taking into account some of the recent drop in incidence. The 

2019 panel also recommended continued monitoring of trends in the incidence rate (including 

external consultation with experts in the private disability industry) and linking the disability 

incidence rate and unemployment rate assumptions. 

In a panel discussion on August 25, 2023, set up by the independent Social Security Advisory 

Board, panelists indicated that both a changing mix of workers by occupation and changing 

demands and accommodations by employers within occupations have contributed to fewer 

workers becoming unable to maintain employment, thus leading to lower levels of disability 

applications. The panelists noted that this appears to be a permanent change. 

The Congressional Budget Office raised their ultimate disability incidence rate to 5.6 per 

thousand for their 2013 through 2015 Long-Term Budget Outlooks and reduced the assumption 

to 5.4 per thousand for their 2016 through 2018 reports, matching the Trustees. For the 2019 

Long-Term Budget Outlook, they reduced the assumption to 5.2 per thousand, again matching 

the Trustees. The 2020-22 Long-Term Budget Outlooks do not explicitly mention the disability 

incidence assumption, so we assume it remained at 5.2 per thousand. CBO reduced the 

assumption to 4.7 per thousand for the 2023 Long-Term Budget Outlook. 

Chart 2 shows age-adjusted historical and long-range alternative II incidence rates for men and 

women. For men, the age-adjusted incidence rate has averaged 4.9 new disability awards per 

thousand exposed workers from 1995 through 2023. The female age-adjusted incidence rate has 

averaged 4.8 per thousand from 1995 through 2023. Since 1980, the age-adjusted incidence rate 

for women has increased to a level much closer to the rate for men. For the 2024 Trustees 

Report, the Trustees assume ultimate age-adjusted disability incidence rates for both men and 

women are 4.5 new disability awards per thousand exposed workers. 

Chart 3 and Chart 4 show the historical and long-range alternative II incidence rates by age 

group for men and women, respectively. The table below shows the 2024 Trustees Report 

alternative II ultimate disability incidence rates by age group. 

Ultimate Disability Incidence Rates per 1,000 Exposed, 2024 Trustees Report Alternative II

Age Group

15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65+ 

Male 0.4 1.2 1.5 1.8 2.4 3.2 4.5 7.7 13.3 16.8 9.3

Female 0.3 0.9 1.3 1.8 2.6 3.8 5.3 8.3 12.9 14.4 8.1

Because the low-cost and high-cost alternative ultimate disability incidence rates are determined 

by adjusting the incidence rates from the intermediate alternative down and up by roughly 20 

percent, respectively, rates for these alternatives are not included in the charts. 
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3 Disability Death Rate 

Death rates are much higher for the disabled population than the general population, as seen in 

Chart 5. Base probabilities of death by duration, age, and sex (from Actuarial Study No. 125) 

are applied to the disabled-worker population. In the first year of the projection period, the death 

rate is determined by fitting an exponential curve to historical death rates for disabled workers by 

age group and sex. For the rest of the projection period, death rate improvement factors are 

applied to the base probabilities of death to reflect the same rate of improvement as the general 

population for that age group and sex. In the 2024 Trustees Report, death rates are assumed to 

remain elevated through 2024 due to the COVID-19 pandemic, and then return to follow the 

underlying declining trend in general population mortality. The age-sex-adjusted death rate 

decreases from 26.8 per thousand beneficiaries in 2023 to 12.4 per thousand in 2098 under the 

intermediate assumptions for the 2024 Trustees Report. 

The disability death rates for the low-cost and high-cost alternatives are determined by 

increasing and decreasing by 7.5 percent, respectively, the death rate in the first year of the 

projection period. Then the general population mortality improvement for that alternative is 

applied to project death rates for the remainder of the 75-year period. 

The 2011 Technical Panel recommended a more rapid decline in disability mortality rates for 

both men and women from 2020 through 2030. The 2015 Technical Panel stated that they were 

comfortable with the Trustees’ assumption. The 2019 Technical Panel did not address this 

assumption. 

4 Disability Recovery Rate 

Beneficiaries stop receiving disability benefits when they (1) die, (2) convert to a retired-worker 

benefit at normal retirement age, (3) recover from their medically-determinable disabling 

condition, or (4) return to work for an extended period. Disabled-worker beneficiaries who return 

to substantial work for an extended period are deemed to have recovered, and their benefits are 

then terminated. The recovery rate is the ratio of the number of terminations for reasons (3) and 

(4) to the average number of disabled-worker beneficiaries during the year. Base probabilities of 

recovery (from Actuarial Study No. 125) by duration, age, and sex are applied to the disabledworker population. 

Chart 6 shows age-sex-adjusted historical and projected alternative II recovery rates. The rate of 

recovery is, at times, affected by budget appropriations for continuing disability reviews, with no 

general upward or downward trend since 1985. The ultimate disability recovery rate under the 

intermediate alternative is equal to the average recovery rate by age group and sex for the years 

1985-2019, excluding 1997. The averaging period was extended through 2019 for the 2024 

Trustees Report. In the 2023 Trustees Report, the averaging period ended in 2005. The 

averaging period begins in 1985, after the Social Security Disability Benefits Reform Act of 

1984 created medical improvement standards for continuing disability reviews. The spike in 

recoveries in 1997 when drug and alcohol addictions were eliminated as bases for disability 

entitlement is excluded from the calculation. 
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The projected age-sex-adjusted recovery rate (medical improvement and return to work) under 

the intermediate assumptions decreases from the relatively high level of 21.0 per thousand 

beneficiaries in 2023 to the ultimate level of 10.8 per thousand beneficiaries under the 

intermediate assumptions for the 2024 Trustees Report. The ultimate recovery rate increased 

from the 10.4 per thousand assumed in the 2023 Trustees Report, reflecting an update to the 

averaging period to use more recent experience. In the 2024 Trustees Report, the recovery rate is 

expected to decrease as the backlog of disabled worker reviews is assumed to be eliminated by 

the end of 2026. Thereafter, the rate decreases toward the expected long-term projected rate. 

Because the low-cost and high-cost alternative ultimate disability recovery rates are determined

by adjusting the recovery rates from the intermediate alternative up and down by roughly 20 

percent, respectively, rates for these alternatives are not included in the chart. 

The 2011 Technical Panel suggested reducing the ultimate alternative II recovery rate 

assumption from 10.7 to 8.7. The 2015 Technical Panel recommended reducing the ultimate 

alternative II recovery rate assumption from 10.4 to 10.1. The 2019 Technical Panel did not 

address this assumption. 

5 Disability Prevalence Rates

The disability prevalence rate is the percentage of the disability insured population that is in 

receipt of disability benefits. Changes in prevalence rates are a direct result of changes in 

incidence rates and termination rates. Age-sex-adjusted prevalence rates have increased 

primarily because: (1) termination rates, in particular death termination rates, have declined; (2) 

incidence rates at younger ages have increased relative to rates at older ages (new beneficiaries at 

younger ages have more potential years on the disability rolls); (3) incidence rates have increased 

substantially for women to parity with men; and (4) the DI program has matured (disabled 

worker benefits became available to those over age 50 at the start of the program in 1957 and to 

younger workers in 1960, and disability insured status requirements were eased for those under 

age 31 in 1968). 

Disability prevalence rates for men rose rapidly prior to 1995 and then less rapidly through 2007, 

as the program matured. Prevalence rates increased later for women, reaching parity with the 

rates for men shortly after 2007. Age-sex-adjusted prevalence rates are now at levels below 

those seen in 2007 and are still declining, in part due to the pandemic. Prevalence rates are 

projected to grow gradually to levels slightly below those seen in 2007 based on the assumed 

stabilization in incidence rates by age and sex at levels above those experienced over the past 10 

years. As incidence rates gradually stabilize, the declining death termination rate continues to 

have a small influence toward higher disability prevalence rates, because applying the same rate 

of reduction in death rates for the disabled as for the general population results in larger declines 

in the death rate for the disabled.

The projected age-sex-adjusted disability prevalence rate grows from 32.7 per thousand 

disability insured at the end of 2023 to 40.3 per thousand at the end of 2098. Chart 7 illustrates 

the historical and projected disabled worker prevalence rates for men and women. The female 

prevalence rate rose close to the level of the male rate around 2007, and is slightly higher than 

the male rate beginning in 2013, because the disability death and recovery rates are generally 
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higher for men than women. In 2098, the age-adjusted prevalence rate is 39.8 for men and 40.8

for women. 

The low-cost and high-cost alternative disability prevalence rates are determined using the 

disability incidence rate, disability death rate, and disability recovery rate assumptions for that 

alternative.
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Chart 1: Effect of the Economy on the DI Incidence Rate

Note: The projections reflect the Trustees’ Assumptions for the 2024 Trustees Report.

Social Security Administration

Office of the Chief Actuary

May 6, 2024
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Chart 2: New Disabled-Worker Awards per 1,000 Exposed (Incidence Rate)

Age-Adjusted (2000)

Note: The projections reflect the Trustees’ assumptions for the 2024 Trustees Report. The dotted lines show the short-range assumptions for the 2024 Trustees 

Report.

Social Security Administration

Office of the Chief Actuary

May 6, 2024
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Chart 3: Male Disabled-Worker Awards per 1,000 Exposed (Incidence Rate) by Age Group

Note: The projections reflect the Trustees’ assumptions for the 2024 Trustees Report. The dotted lines show the short-range assumptions for the 2024 Trustees 

Report.

Social Security Administration

Office of the Chief Actuary

May 6, 2024
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Chart 4: Female Disabled-Worker Awards per 1,000 Exposed (Incidence Rate) by Age Group

Note: The projections reflect the Trustees’ assumptions for the 2024 Trustees Report. The dotted lines show the short-range assumptions for the 2024 Trustees 

Report.

Social Security Administration

Office of the Chief Actuary

October 13, 2023

Social Security Administration

Office of the Chief Actuary

May 6, 2024
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.

Chart 5: Age-Sex-Adjusted Comparison of SSA General Population Mortality to Disabled Worker Mortality

Note: The projections reflect the Trustees’ assumptions for the 2024 Trustees Report. 

Social Security Administration

Office of the Chief Actuary

May 6, 2024
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Chart 6: Disabled-Worker Recoveries per 1,000 Beneficiaries

Age-Sex-Adjusted (2000)

Note: The projections reflect the Trustees’ assumptions for the 2024 Trustees Report. The dotted lines show the short-range assumptions for the 2024 Trustees 

Report.

Social Security Administration

Office of the Chief Actuary

May 6, 2024
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Chart 7: Disabled-Worker Prevalence Rates through NRA (per 1,000 Insured Population)

Age-Adjusted to the 2000 Insured Population

Note: The projections reflect the Trustees’ assumptions for the 2024 Trustees Report. The dotted lines show the short-range assumptions for the 2024 Trustees

Report.

Social Security Administration

Office of the Chief Actuary

May 6, 2024