ATTRITION BIAS IN PANEL ESTIMATES OF THE 

CHARACTERISTICS OF PROGRAM BENEFICIARIES 

John L. Czajka 

James Mabli 

Karen Cunnyngham 

Mathematica Policy Research, Inc. 

600 Maryland Ave., SW, Suite 550 

Washington, DC 20024 

jczajka@mathematica-mpr.com 

jmabli@mathematica-mpr.com 

kcunnyngham@mathematica-mpr.com 

1.0 Introduction

Attrition is a fact of life in panel surveys, but attrition presents a more serious problem in some panel surveys than others. 

The Census Bureau’s inability to reduce attrition to an acceptable level was cited as the leading factor in the agency’s 

decision to phase out the Survey of Income and Program Participation (SIPP) and replace it with a new data collection system 

(U.S. Census Bureau 2006). While the Census Bureau subsequently reversed its decision to collect no additional SIPP data 

after September 2006, lower attrition rates have been defined as a means of achieving the goal of improved accuracy in the 

reengineering of SIPP (Johnson 2007). 

With each successive interview, fewer members of an initial SIPP panel respond. Excluding those who have left the SIPP 

universe, this attrition of panel members may make the sample less representative of the survivors of the population from 

which the initial sample was selected. There is ample evidence from numerous studies over the years that people who attrite 

from panel surveys—including the SIPP—are different from people who continue to respond. However, SIPP sample 

weights—both cross-sectional and longitudinal—incorporate rather substantial adjustments designed to reduce the bias that 

may result from attrition. This study looks at the effectiveness of the adjustments that are included in the Census Bureau’s 

weights and whether any refinement of these adjustments could be beneficial to applications of SIPP panel data by the Social 

Security Administration (SSA). 

2.0 Attrition in the SIPP 

We can measure the magnitude of attrition over the full length of a SIPP panel in different ways, depending on whether our 

perspective is longitudinal or cross-sectional. We focus on the longitudinal weights—specifically, the full panel weight that 

is assigned to panel members who responded to all interviews for which they remained in the survey universe. To qualify for 

a full panel weight, a sample member must be present in the common month of the first wave (January 2001 for the 2001 

panel) and have data for all subsequent months through the final reference month of the last wave unless the sample member 

left the survey universe. Sample members who leave the SIPP universe can qualify for full panel weights if they have data 

for all months for which they remained in the survey universe. (In effect, the absence of reported information for a sample 

member who is no longer in the survey universe is still “data.”) Sample members can complete the final interview of a SIPP 

panel without qualifying for full panel weights, owing to missed interviews along the way. By completing the final 

interview, or any given interview, they qualify for cross-sectional weights for the reference period covered by that interview. 

The proportion of SIPP panel members qualifying for cross-sectional weights for both the initial wave and final wave is 

considerably higher than the proportion qualifying for full panel weights. 

Table 1 presents unweighted sample counts and unweighted proportions of wave 1 sample members retained through the end 

of the 1996 and 2001 SIPP panels, as well as the weighted estimates, based on alternative definitions of retention. The 

weighted proportions differ little from the unweighted proportions, so we focus on the unweighted estimates. 

For the 9-wave 2001 panel, 64.4 percent of the wave 1 respondents present in January 2001 qualified for full panel weights, 

implying an attrition rate of 35.6 percent. For the 12-wave 1996 panel, 58.3 percent of the wave 1 respondents qualified for a 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

full panel weight. For comparability, we applied a 9-wave panel definition to the 1996 panel and found that 63.7 percent 

would appear to have qualified for a 9-wave full panel weight. This is not a perfect proxy for retention in a 9-wave panel 

because the Census Bureau does not assign a full panel weight to everyone who would appear to qualify, so we applied the 

same definition to the 2001 panel and found that 64.8 percent satisfied these marginally broader criteria. By this measure, 

sample retention was somewhat higher (attrition was somewhat lower) in the 2001 panel than the 1996 panel. 

By a less restrictive measure of sample retention, 72.5 percent of the 1996 panel and 78.5 percent of the 2001 panel was 

interviewed in both the first and ninth waves, implying attrition rates of 27.5 versus 21.5 percent. The markedly lower 

attrition in the 2001 panel is due to a survey operational change initiated with the 2001 panel. Previously, interviews were 

not attempted with sample members who missed two consecutive waves (or three, depending on the reason). Beginning with 

the 2001 panel, sample members were no longer dropped from the active sample if they missed consecutive interviews. 

While this change in practice had no impact on the proportion qualifying for full panel weights, it had a pronounced impact 

on the proportion of the original sample that was interviewed in the final (ninth) wave. If we include sample members who 

missed the wave 9 interview but responded to the wave 8 interview—and, therefore, would not have been counted as attriters 

even in the 1996 panel—the retention rate rises (and the attrition rate declines) by two percentage points in each panel. 

3.0 Attrition among Social Security Beneficiaries

Attrition rates for social security beneficiaries other than SSI recipients are markedly lower than those for the total 

population. This is due primarily to their older age distribution. Only 24.4 percent of the social security retired workers in 

the wave 1 sample of the 2001 SIPP panel failed to qualify for full panel weights, and only 14.3 percent did not complete 

wave 9 (Table 2).1 If we were to impute the bounded missing waves for those who completed waves 1 and 9 but failed to 

qualify for full panel weights, we would reduce the proportion who failed to qualify for full panel weights to 17.7 percent.2 

Attrition rates are somewhat higher for disabled workers (ranging from 18.4 percent to 27.9 percent) and all other social 

security beneficiaries (16.8 percent to 27.3 percent). For SSI recipients, the attrition rates range from 20.9 percent to 33.7 

percent, which is very close to the total population. Among persons who were 65 and older in January 2001, however, there 

is little difference across the beneficiary subpopulations and the total population—especially after imputation of missing 

waves. 

Elderly sample members were less likely to qualify for full panel weights in the 1996 panel than the 2001 panel (Table 2). 

Therefore, attrition rates based on the assignment of full panel weights were a few percentage points higher for social security 

beneficiaries in the 1996 panel than the 2001 panel. For example, 28.8 percent of retired workers failed to qualify for full 

panel weights in the 1996 panel compared to 24.4 percent in the 2001 panel. The difference between the two panels is even 

more pronounced when we compare the proportions of wave 1 respondents who did not respond to wave 9. By this measure 

the attrition rate among retired workers in the 1996 panel was 22.4 percent versus 14.3 percent in the 2001 panel. For 

disabled workers these rates were 23.4 percent (1996) and 18.4 percent (2001), and for all other social security beneficiaries 

they were 23.3 percent (1996) and 16.8 percent (2001). For SSI recipients, with their broader age range, the comparable 

figures were 23.3 percent (1996) and 20.9 percent (2001). 

Because of the aforementioned change in operational procedures, the proportion of sample members failing to complete the 

ninth interview is clearly less of a problem in the 2001 panel than the 1996 panel, and this is true across the board. In fact, by 

this measure the 2001 panel is more similar to the 1993 panel than to the 1996 panel. The 21.3 percent attrition rate for the 

full 2001 sample compares to a 19.2 percent attrition rate for the 1993 panel versus 27.5 percent for the 1996 panel. For all 

social security or SSI beneficiaries, the 16.0 percent attrition rate in the 2001 panel compares to a 13.5 percent attrition rate in 

the 1993 panel versus 23.0 percent in the 1996 panel. 

1 These estimates are weighted. Compare to Table 1. 

2 With the 1996 panel the Census Bureau ceased production of a longitudinal file and discontinued the imputation of 

missing waves, which had been initiated with the 1991 panel. MPR has produced its own missing wave imputations for the 

1996 and 2001 panel. Our estimates of who would fail to qualify as full panel members with the imputation of missing 

waves are based on the results of this work. For 1993, the percentages who would not qualify as full panel members with or 

without imputation of missing waves are based on the Census Bureau’s missing wave imputations. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.0 Bias in Full Panel Estimates of Earnings

Vaughan and Scheuren (2002) and Hall et al. (2004) added to the literature on differences between attriters and continuers 

with extensive analyses using SIPP and Survey of Program Dynamics (SPD) data linked to summary earnings record (SER) 

data.3 Our focus in this report is different. We acknowledge that there are important differences between attriters and 

continuers, but the question of interest to us is whether differences exist between the full panel (continuers) and the full crosssectional sample (continuers plus attriters) after the application of non-interview adjustments and demographic calibration 

designed to reduce or eliminate specific types of differences between the full panel and the cross-sectional sample. 

A limitation of the analysis of the 2001 SIPP panel arises from the fact that SSNs were not requested until the second and 

later interviews. Because of this, there are no matched data for persons who attrited immediately after the first wave. This 

means that when we compare the matched full panel sample with the matched wave 1 cross-sectional sample, the sample 

members who attrited after wave 1 are excluded from both groups. This removes about a quarter of the total attrition from 

the evaluation with administrative records. 

Using SIPP data matched to the SER, we compared distributions of earnings between the full panel sample and the wave 1 

respondents who also responded to wave 2 (and were asked for their SSNs). The wave 1/wave 2 sample serves as a proxy for 

the wave 1 cross-sectional sample. To correct in a simple way for match bias, both samples were calibrated to the population 

totals that the Census Bureau used to calibrate the January 2001 cross-sectional sample and the full panel. 

The upper panel of Table 3a reports the wave 1/wave 2 estimates of the proportion of persons with positive SER earnings, by 

age, for each of the years 1999 through 2003. An advantage of using administrative records in evaluating attrition bias is that 

we are not limited to the survey period (although SSA’s analytical use of SIPP full panel data linked to administrative records 

would be limited to the time frame of the survey). The lower panel of the table reports the difference between the full panel 

and wave 1/wave 2 estimate of each proportion, with indicators of statistical significance. For persons 18 to 24, the full panel 

estimates are about a percentage point lower than the cross-sectional sample estimates across all years, and the largest of 

these differences (in 2000 and 2001) are statistically significant at the 0.05 level or better. Outside of this age group, the 

differences are negligible, and none is significant at the 0.05 level or better. 

Tables 3b and 3c report the wave 1/wave 2 estimates of points in the distribution of earnings among those with positive 

earnings, by age, in each of the five years, as well as differences between the full panel and wave 1/wave 2 estimates, with 

indicators of statistical significance. Except for one age group (65+) in one year (2002), mean positive earnings among panel 

members 45 and older are consistently lower than the estimates from the wave 1/wave 2 sample, and half of the differences in 

mean earnings among workers 55 and older are large enough to be statistically significant at the 0.10 level or better. Median

earnings are also lower, generally, for panel members 45 and older, but the difference is not statistically significant in any age 

group and year. It is evident from Table 3c that the differences in means are driven by the upper part of the earnings 

distribution. Panel estimates of the 75th percentile are consistently lower than the wave 1/wave 2 estimates among workers 

35 to 64, The differences are statistically significant among workers 55 to 64 in three of the five years. 

It is surprising that where we find differences in positive earnings, the panel sample (after the Census Bureau’s attrition 

adjustment) has a lower incidence of high earnings than the cross-sectional sample. This runs counter to research findings 

that attrition probabilities are highest among those with very low income. Together these findings suggest that the Census 

Bureau’s adjustments generally compensate for attrition bias with respect to income. Among older workers, the adjustments 

appear to over-correct for attrition bias by producing more high-income workers than were lost to attrition . 

Lastly, Table 4 compares the matched wave 1/wave 2 and full panel samples with respect to the gross change in annual 

earnings between 2001 and 2003. The upper part of the table reports the (weighted) proportion of persons in the wave 

1/wave 2 sample with a positive change, no change, or negative change in earnings between the two years. Persons with zero 

earnings in either year are excluded . Among all persons 18 and older, 60.9 percent experienced an increase in earnings and 

39.1 percent incurred a reduction in earnings. Positive changes peak in the youngest age group and decline with increasing 

3 The SER contains the annual earnings (from both wage and salary and self-employment) on which Social Security 

taxes were paid and which are used to calculate social security benefit entitlements. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

age. Table 5 presents a frequency distribution of the magnitudes of the changes whose signs are measured in Table 4. Most 

of the individuals who experience a positive change in earnings between 2001 and 2003 incur more than a 25 percent change 

in earnings. Similarly, most of the individuals who experience a negative change in earnings across years have their earnings 

decrease by more than 25 percent. 

The lower portion of Tables 4 and 5 reports the difference between the matched full panel and wave 1/wave 2 samples. 

Among persons 18 and older, full panel members were significantly more likely than cross-sectional sample members to 

experience an increase in earnings, but the difference was less than a percentage point. Differences are very slightly larger 

and still significant among persons 25 to 34, but there are no significant differences at ages 35 and older. Where Vaughan 

and Scheuren found that attriters experienced greater increases in earnings than nonattriters, we find that when the sample

weights are adjusted for attrition bias, it’s the full panel sample—the non-attriters—who are somewhat more likely to 

experience an increase in earnings over the duration of the panel, suggesting that, if anything, the Census Bureau’s weighting 

adjustments for attrition bias may overcompensate for the bias arising from attrition. When we compare the magnitudes of 

the change in earnings, we find that full panel members 18 to 64 were significantly less likely to have experienced a large 

decline in earnings but were no more likely than cross-sectional sample members to have experienced a large increase in 

earnings—or any change beyond a large decline. In short, by this measure of gross change in earnings, full panel members as 

a whole were quite similar to cross-sectional sample members. 

5.0 Bias in Full Panel Estimates of Social Security Beneficiaries

To assess the bias in full panel estimates of Social Security beneficiaries, we compared the full panel and wave 1/wave 2 

samples with respect to characteristics obtained from the Social Security Master Beneficiary Record enhanced with payment 

data from the Payment History Update System (MBR-PHUS). 

The full panel and wave 1/wave 2 samples produce nearly identical estimates of the number of Social Security beneficiaries 

in January 2001 and their distribution by type of beneficiary and age (Table 6). For example, on an estimate of 28 million 

retired workers, the two samples differ by only 56,000. And on an estimate of 5 million disabled workers, the two samples 

differ by only 23,000. Larger differences occur for the smaller aged non-widow and all other beneficiary populations, but 

only the difference of 99,000 for an estimate of 2 million aged non-widows is statistically significant—and only at the 0.10 

level. 

Larger differences emerge by the end of the panel (September 2003), but even here only one category has differences that are 

statistically significant. Out of 30 million retired worker beneficiaries the two samples differ by about one-third of a million 

(Table 6). For all beneficiaries, the full panel is 405,000 or less than 1 percent below the wave 1/wave 2 estimate of 45.5 

million, a difference that is statistically significant at the 0.01 level. 

Since SIPP is a longitudinal survey, how well it captures important life transitions is of great interest to users. Transitions 

into and out of each beneficiary status category, as well as the differences in these transitions between the full panel and the 

wave 1/wave 2 sample, are estimated in Table 7. The first and fourth columns are the January 2001 and September 2003 

category totals from Table 6. The second and third columns contain estimates of the number of individuals who enter into or 

exit from each beneficiary category between January 2001 and September 2003. The full panel and wave 1 / wave 2 samples 

produce nearly identical estimates of these transitions. The only transition for which there is a statistically significant 

difference (at the 0.05 level) involves retired workers who receive a benefit in January 2001 but no longer receive a 

retirement benefit in September 2003. In this case, the full panel estimate is approximately 7 percent greater than the wave 1 

/ wave 2 estimate. Additionally, the number of entrants into all beneficiary categories is 249,000 lower in the full panel than 

in the cross-sectional sample. While the difference is statistically significant at the 0.01 level, it is less than 3 percent of the 

wave 1 / wave 2 entrant total of 8.5 million. 

Table 8 reports the mean amounts of several administrative variables that are related to the primary insurance amount among 

disabled and retired workers, based on the matched wave 1/wave 2 observations, as well as the differences in means between 

the full panel and the wave 1/wave 2 sample. For disabled workers, these differences are negligible, and none is statistically 

significant at the 0.10 level. For retired workers, there are only negligible differences between the two samples although five 

of them, ranging from $5 to $6, are statistically significant at the 0.10 level. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6.0 Bias in Full Panel Estimates of SSI Recipients

To assess the bias in full panel estimates of SSI recipients, we compared the full panel and wave 1/wave 2 samples with 

respect to characteristics obtained from the Supplemental Security Record (SSR). 

Estimates of the number, type (age, blind, or disabled), and age distribution of SSI recipients also differ little between the full 

panel and the wave 1/wave 2 cross-section (Table 9). In both January 2001 and September 2003 the full panel finds more 

disabled beneficiaries age 25 to 49 than the wave 1/wave 2 sample; the difference is about 100,000 out of 2 million, or a little 

less than 5 percent, but it is not statistically significant. This difference grows to 143,000 in September 2003 but still falls 

short of statistical significance. In other age groups the differences are proportionally similar except among persons 65 and 

older, where the difference in both years is much smaller. Differences between the two samples are not statistically 

significant for any age group and eligibility category pair, although it should be noted that the sample of blind recipients is 

too small to support statistically significant differences. 

Table 10a contains estimates of the means of federal and state payment variables as well as two determinants of the payment 

variables, earned and unearned income. Differences in the mean amounts between the two samples are generally small, only 

a few are statistically significant, and they form no obvious pattern. The mean of the federal SSI benefit over all age groups 

is about 4 percent greater in the full panel sample than in the cross-sectional sample in January 2001. For 25-49 year old 

beneficiaries, the mean federal SSI benefit is about 7 percent greater in the full panel sample than in the cross-sectional 

sample in January 2001. Both differences are statistically significant at the 0.10 level. Estimates from the two samples are

even closer in September 2003 than in January 2001. 

The two samples are also quite similar with respect to the gross change in a number of the payment variables recorded on the 

SSR (see Table 10b). For all recipients and elderly recipients, the largest differences lie in the 1 to 2 percentage point range. 

None of the differences for elderly recipients is statistically significant. Differences for recipients under age 65 are somewhat 

larger than this for three of the four variables, and differences for earned income and the federal benefit amount are 

statistically significant. When the age groups are combined we find statistically significant differences for these same two 

variables. Overall, though, the small magnitudes of the differences between the two samples and the absence of a strong 

pattern in these differences are more compelling. We note, for example, that the largest differences run in opposite directions 

for the nonelderly and elderly beneficiaries. 

Table 11 presents estimates of the distribution of SSI payments as a percentage of personal income in January 2001 for all 

SSI recipients and for subgroups defined by selected demographic characteristics. In both the numerator and denominator of 

this percentage, the benefit amount reported in the SIPP has been replaced by the amount recorded in the SSR. Differences 

between the full panel and wave 1/wave 2 samples are reported in the right hand side of the table. The two samples are 

nearly identical for all SSI recipients, with no statistically significant differences For several demographic groups, there are 

statistically significant differences between the samples, but the differences are scattered, suggesting no particular pattern, 

and they rarely exceed 3 percentage points. 

7.0 Conclusion and Recommendations

When measured in terms of the proportion of wave 1 respondents who could not be assigned full panel weights, attrition got 

no worse between the 1996 and 2001 panels. Among older social security beneficiaries and older persons generally, attrition 

of this type was actually lower in the 2001 panel than the 1996 panel. Furthermore, because of an operational change, the 

proportion of the wave 1 sample failing to complete the wave 9 interview declined markedly between the 1996 and 2001 

panels, to the point where the 2001 panel resembled the 1993 panel more closely than it resembled the 1996 panel in this 

alternative measure of attrition. These developments suggest that the upturn in attrition between the 1993 and 1996 panels 

did not continue through the 2001 panel. If growing attrition is a concern, there is actually less reason to hesitate in using the 

2001 panel than the 1996 panel. 

An analysis of earnings data from SER records matched to SIPP records suggests that the attrition adjustments that the 

Census Bureau applies to its panel and post-wave 1 cross-sectional weights are effective in correcting for attrition bias with 

respect to income. The limited number of significant differences that we observed between the panel sample and the wave 1 

sample members who provided SSNs in wave 2 were in the opposite direction as the attrition bias documented elsewhere. 

Among persons 50 to 61, the panel sample tended to underestimate the frequency of high earnings, but there were no 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

consistent differences elsewhere and no consistent differences in the proportion of persons who had positive earnings. 

Estimates of gross changes in earnings also differ little between the full panel and wave 1/wave 2 cross-sectional samples. 

Estimates of the number and selected characteristics of Social Security and SSI beneficiaries show only small differences 

between the full panel and wave 1/wave 2 samples. This is particularly striking for estimates of transitions into and out of 

Social Security beneficiary categories, estimates of payment amounts for retired and disabled workers, and estimates of the 

proportion of SSI beneficiaries’ personal income that is provided by their SSI benefits. 

In all, these findings based on data from three administrative data sources suggest that for the population of Social Security 

and SSI beneficiaries, the full panel could readily substitute for the wave 1/wave 2 sample. 

References 

Hall, David, Smanchai Sae-Ung, and Jan Tin. “Earned Income and Longitudinal Attrition in the SIPP and SPD.” 

Proceedings of the Survey Research Methods Section. Alexandria, VA: American Statistical Association, 2004. 

Johnson, David. “Reengineering the SIPP: The Evolution of a Phoenix.” Presentation at the Joint Statistical Meetings, Salt 

Lake City, UT, August 2007. 

U.S. Census Bureau. “The Phase-Out of the Survey of Income and Program Participation (SIPP) and the Launch of the 

Program of Income, Wealth, and Health Insurance Measurement.” Washington, DC, February 3, 2006. 

Vaughan, Denton R. and Fritz Scheuren. “Longitudinal Attrition in the SIPP and SPD.” Proceedings of the Survey Research

Methods Section. Alexandria, VA: American Statistical Association, 2002. 
TABLE 1

SIPP PANEL RETENTION BY ALTERNATIVE DEFINITIONS, UNWEIGHTED AND WEIGHTED ESTIMATES:

1996 AND 2001 SIPP PANELS

Sample Counts Retention Rate Attrition Rate

Definition of Retention 1996 2001 1996 2001 1996 2001

Persons in wave 1 common month 95,141 77,269 100.0 100.0 0.0 0.0

Number of these with:

 Full panel weight 55,484 49,749 58.3 64.4 41.7 35.6

 Pseudo 9-wave panel eligibility 60,641 50,099 63.7 64.8 36.3 35.2

 Wave 9 data or full panel weight 68,992 60,620 72.5 78.5 27.5 21.5

 Wave 8 or wave 9 data or full panel weight 70,549 62,184 74.2 80.5 25.8 19.5

Weighted

Estimates (1,000s) Retention Rate Attrition Rate

Definition of Retention 1996 2001 1996 2001 1996 2001

Persons in wave 1 common month 264,254 279,185 100.0 100.0 0.0 0.0

Number of these with:

 Full panel weight 154,264 180,352 58.4 64.6 41.6 35.4

 Pseudo 9-wave panel eligibility 168,594 181,704 63.8 65.1 36.2 34.9

 Wave 9 data or full panel weight 191,472 219,611 72.5 78.7 27.5 21.3

 Wave 8 or wave 9 data or full panel weight 195,790 224,615 74.1 80.5 25.9 19.5

Source: Mathematica Policy Research, from the 1996 and 2001 SIPP panels.

Note: The 1996 panel included 12 waves; the 2001 panel included only 9 waves. The weighted estimates for 2001

 are based on the full January 2001 cross-sectional weight, adjusted for a one-third sample cut after wave 1.
TABLE 2

WEIGHTED ATTRITION RATE (PERCENT) AFTER WAVE 1 AMONG ALL PERSONS AND SOCIAL SECURITY OR SSI BENEFICIARIES

BY AGE, WITH OR WITHOUT MISSING WAVE IMPUTATIONS OR COMPLETE WAVE 9 DATA

2001 Panel (Age in January 2001) 1996 Panel (Age in March 1996)a

1993 Panel (Age in January 1993)

Subtotal Subtotal Subtotal Subtotal Subtotal Subtotal

Population Total Under 65 65+ Total Under 65 65+ Total Under 65 65+

Percentage Not Qualifying as Full Panel Members with No Missing Wave Imputations

Total Population 35.4 36.9 24.5 36.6 37.6 28.7 28.4 29.8 18.3

Unduplicated Total Beneficiaries 26.5 31.5 24.2 29.9 32.9 28.5 20.5 27.2 17.8

Retired Workers 24.4 27.2 24.0 28.8 30.3 28.6 18.5 23.9 17.8

Disabled Workers 27.9 29.8 21.9 29.7 31.3 25.3 24.6 25.3 22.7

All Other Social Security Beneficiaries 27.3 32.1 24.2 31.1 34.1 29.2 19.8 26.2 17.6

SSI Beneficiaries 33.7 35.9 26.2 30.7 34.1 22.3 25.9 31.1 16.6

Percentage Not Qualifying as Full Panel Members with Imputation of Missing Waves

Total Population 27.4 28.7 18.1 32.9 33.9 25.8 23.6 25.0 13.4

Unduplicated Total Beneficiaries 19.8 23.9 17.9 27.1 29.8 25.8 15.9 22.9 13.0

Retired Workers 17.7 18.9 17.6 26.0 25.3 26.0 13.6 18.9 12.9

Disabled Workers 22.5 23.9 17.9 28.2 29.0 26.0 20.1 20.8 18.2

All Other Social Security Beneficiaries 20.9 24.5 18.6 27.5 30.5 25.7 15.0 21.8 12.8

SSI Beneficiaries 26.0 27.9 19.5 30.0 33.1 22.3 23.3 28.0 14.8

Percentage Not Qualifying as Full Panel Members or with Data for All Four Months of Wave 9

Total Population 21.3 22.2 14.7 27.5 28.3 22.3 19.2 20.1 11.8

Unduplicated Total Beneficiaries 16.0 19.2 14.5 23.0 24.7 22.3 13.5 18.6 11.5

Retired Workers 14.3 14.4 14.3 22.4 22.2 22.5 11.8 15.3 11.4

Disabled Workers 18.4 19.4 15.3 23.4 24.6 20.0 16.8 16.9 16.5

All Other Social Security Beneficiaries 16.8 19.6 15.0 23.3 25.0 22.3 12.8 17.5 11.2

SSI Beneficiaries 20.9 22.8 14.6 23.3 25.9 16.6 19.5 23.5 12.2

Source: Mathematica Policy Research, from the 1993, 1996 and 2001 SIPP panels.

Note: Attrition rates are weighted by the January 2001, March 1996, and January 1993 cross-sectional weights for the 2001, 1996, and 1993 estimates,

 respectively.

a

 All 1996 estimates are based on a simulated 9-wave panel. See text for details.
 

 

 

TABLE 3A

PROPORTION OF PERSONS WITH POSITIVE EARNINGS IN THE SER

BY AGE AND CALENDAR YEAR

Age in January 1999 2000 2001 2002 2003

Wave 1 Sample with Wave 2 and Matched Data

18+ 70.6 70.8 69.9 68.2 67.1

18-24 85.8 87.6 87.1 85.3 83.8

25-34 85.7 86.5 86.0 84.1 84.0

35-44 83.2 83.8 83.5 81.8 81.2

45-54 78.6 79.6 79.2 78.4 77.8

55-64 60.5 60.8 60.8 61.1 61.0

65+ 16.1 16.2 15.4 15.3 14.6

Difference between Full Panel Sample with Matche Data

and Wave 1 Sample with Wave 2 and Matched Data

18+ -0.3 * -0.3 -0.2 0.0 0.0

18-24 -0.8 -1.1 ** -1.4 *** -0.7 -0.9 *

25-34 0.1 -0.1 -0.2 0.0 0.2

35-44 -0.5 * -0.2 -0.3 0.0 -0.2

45-54 -0.3 -0.2 0.4 0.3 0.3

55-64 -0.2 0.1 0.1 0.6 0.5

65+ 0.1 0.2 0.1 -0.1 0.0

Source: Mathematica Policy Research, from linked 2001 SIPP-SER records.

Note: All earnings have been adjusted for inflation and are in 2001 dollars.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

 * Statistically significant at 0.10 level
 

 

 

 

TABLE 3B

MEAN AND MEDIAN ANNUAL EARNINGS OF WORKERS WITH POSITIVE EARNINGS 

IN THE SER, BY AGE AND CALENDAR YEAR

Age in January 1999 2000 2001 2002 2003

Mean Earnings

Wave 1 Sample with Wave 2 and Matched Data

18+ 27,756 28,131 28,308 28,637 28,628

18-24 12,952 13,282 12,989 12,846 12,421

25-34 27,355 28,268 28,557 28,707 28,279

35-44 32,662 33,027 33,185 33,662 33,821

45-54 35,057 35,077 35,289 35,790 36,165

55-64 29,139 29,132 29,914 30,766 30,855

65+ 13,610 13,955 14,669 14,611 14,799

Difference between Full Panel Sample with Matched Data and

 Wave 1 Sample with Wave 2 and Matched Data

18+ -64 -84 -93 -57 -17

18-24 105 108 -161 -201 -174

25-34 -153 -34 66 194 370

35-44 8 -217 -110 -165 46

45-54 -104 -181 -329 -227 -216

55-64 -558 ** -196 -471 -480 * -598 **

65+ -697 * -796 ** -397 43 -142

Median Earnings

Wave 1 Sample with Wave 2 and Matched Data

18+ 22,986 23,308 23,400 23,457 23,415

18-24 10,382 10,588 9,987 10,182 9,722

25-34 24,088 24,827 25,150 25,287 24,962

35-44 29,220 29,225 29,005 29,112 29,284

45-54 30,983 30,817 31,231 31,453 31,835

55-64 23,436 23,368 24,215 24,473 24,218

65+ 7,083 7,341 8,366 7,877 8,355

Difference between Full Panel Sample with Matched Data and

 Wave 1 Sample with Wave 2 and Matched Data

18+ 62 72 27 74 154

18-24 324 184 -173 -247 -458

25-34 -66 60 48 468 255

35-44 88 -190 -81 -375 166

45-54 19 -103 -478 -229 -128

55-64 -495 367 -217 -213 -210

65+ -14 -54 -124 13 65

Source: Mathematica Policy Research, from linkded 2001 SIPP-SER records.

Note: All earnings have been adjusted for inflation and are in 2001 dollars.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

 * Statistically significant at 0.10 level
 

 

 

 

 

 

 

 

 

 

 

 

 

TABLE 3C

25TH AND 75TH PERCENTILES OF ANNUAL EARNINGS OF WORKERS WITH

POSITIVE EARNINGS IN THE SER, BY AGE AND CALENDAR YEAR

Age in January 1999 2000 2001 2002 2003

25th Percentile of Earnings

Wave 1 Sample with Wave 2 and Matched Data

18+ 10,361 10,565 10,339 10,328 10,090

18-24 4,375 4,331 4,360 4,024 3,623

25-34 12,490 13,068 13,169 13,110 12,687

35-44 14,937 14,941 14,875 14,661 14,807

45-54 16,805 17,004 17,024 17,412 17,362

55-64 10,022 10,257 10,493 10,616 10,736

65+ 2,231 2,166 2,403 2,569 2,737

Difference between Full Panel Sample with Matched Data and

 Wave 1 Sample with Wave 2 and Matched Data

18+ 189 154 71 144 137

18-24 140 106 -319 ** -121 -166

25-34 -14 120 173 232 532 *

35-44 356 428 125 114 333

45-54 234 153 -337 13 121

55-64 155 320 210 59 -43

65+ -20 -12 -3 170 -249

75th Percentile of Earnings

Wave 1 Sample with Wave 2 and Matched Data

18+ 39,545 40,129 40,403 40,805 40,730

18-24 18,626 19,312 18,956 18,787 18,190

25-34 37,311 38,863 39,193 39,465 38,338

35-44 46,252 46,799 46,640 47,574 48,248

45-54 50,057 50,199 50,106 50,194 51,083

55-64 42,427 41,678 43,440 45,096 45,164

65+ 15,445 16,941 16,929 17,685 18,022

Difference between Full Panel Sample with Matched Data and

 Wave 1 Sample with Wave 2 and Matched Data

18+ -233 -333 * -387 -268 -222

18-24 204 163 -24 -229 -74

25-34 -312 -588 -168 69 336

35-44 0 -628 -598 -542 -820

45-54 -298 -646 -382 -443 -759

55-64 -1,205 * -749 -1,844 ** -1,233 -1,552 **

65+ -616 -923 -285 202 392

Source: Mathematica Policy Research, from linked 2001 SIPP-SER records.

Note: All earnings have been adjusted for inflation and are in 2001 dollars.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

 * Statistically significant at 0.10 level
TABLE 4

PROPORTION OF PERSONS WITH A CHANGE IN SER ANNUAL EARNINGS,

BY DIRECTION, 2001 TO 2003: PERSONS WITH

POSITIVE EARNINGS IN BOTH YEARS

Positive No Negative

Age in January 2001 Change Change Change

Wave 1 Sample with Wave 2 and Matched Data

18+ 60.9 0.0 39.1

18-24 67.2 0.0 32.8

25-34 62.9 0.0 37.1

35-44 62.2 0.0 37.8

45-54 59.8 0.0 40.2

55-64 50.8 0.0 49.2

65+ 39.2 0.0 60.8

Difference between Full Panel Sample with

Matched Data and Wave 1 Sample with

Wave 2 and Matched Data

18+ 0.7 *** 0.0 a

-0.7 ***

18-24 1.1 0.0 a

-1.1

25-34 1.3 ** 0.0 a

-1.3 **

35-44 0.5 0.0 a

-0.5

45-54 0.1 0.0 a

-0.1

55-64 0.4 0.0 a

-0.4

65+ 0.3 0.0 a

-0.3

Source: Mathematica Policy Research, from linked 2001 SIPP-SER records.

Note: All earnings have been adjusted for inflation and are in 2001 dollars.

a

 Since the cross-sectional sample estimate is zero, the full panel estimate is

 zero as well.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

 * Statistically significant at 0.10 level
 

 

 

 

 

 

 

TABLE 5

FREQUENCY DISTRIBUTION OF GROSS CHANGE IN SER ANNUAL EARNINGS,

2001 TO 2003, BY AGE: PERSONS WITH POSITIVE EARNINGS BOTH YEARS

(Thousands of Persons)

Age in January 2001 Percentage Change in 

Earnings 18+ 18 to 64 65+

Wave 1 Sample with Wave 2 and Matched Data

(More than -25.0%) 23,442 22,182 1,260

(-10.1% to -25.0%) 10,556 10,096 460

(-5.1% to -10.0%) 6,408 6,225 183

(-2.1% to -5.0%) 6,219 5,954 265

(-0.1% to -2.0%) 4,397 4,252 145

0 0 0 0

(0.1% to 2.0%) 5,001 4,922 79

(2.1% to 5.0%) 14,487 14,194 293

(5.1% to 10.0%) 11,063 10,889 174

(10.1% to 25.0%) 18,030 17,763 267

(More than 25.0%) 30,949 30,269 680

Difference between Full Panel Sample with

Matched Data and Wave 1 Sample with

Wave 2 and Matched Data

(More than -25.0%) -1,153 *** -1,137 *** -15

(-10.1% to -25.0%) -220 -221 1

(-5.1% to -10.0%) 145 138 7

(-2.1% to -5.0%) 225 233 * -8

(-0.1% to -2.0%) 33 21 12

0

a

0

a

0

a

0

(0.1% to 2.0%) 188 192 -4

(2.1% to 5.0%) 130 131 -1

(5.1% to 10.0%) 530 *** 523 *** 6

(10.1% to 25.0%) 235 227 8

(More than 25.0%) -393 -401 8

Source: Mathematica Policy Research, from linked 2001 SIPP-SER records.

Note: All earnings have been adjusted for inflation and are in 2001 dollars.

a

 Since the cross-sectional sample estimate is zero, the full panel estimate is zero

 as well.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level
 

 

 

 

 

 

TABLE 6

DISTRIBUTION OF SOCIAL SECURITY BENEFICIARY STATUS IDENTIFIED IN THE MBR, BY AGE:

JANUARY 2001 AND SEPTEMBER 2003

(Thousands of Persons)

Disabled Retired Aged Aged All Other

Age Worker Worker Non-widow Widow Beneficiaries Total

Wave 1 Sample with Wave 2 and Matched Data

January 2001:

5,000 2,620 240 334 3,986 12,180

0 25,435 1,720 3,107 21 30,283

 Under 65

 65 and older

 Total 5,000 28,055 1,960 3,441 4,007 42,462

September 2003:

5,895 2,861 117 416 4,145 13,434

0 27,190 1,681 3,181 24 32,077

5,895 30,051 1,799 3,597 4,169 45,511

 Under 65

 65 and older

 Total

Difference between Full Panel Sample with Matched Data and

Wave 1 Sample with Wave 2 and Matched Data

January 2001:

 Under 65 23 29 -18 23 137 193

 65 and older

 Total

0

a

-84 -80 23 0 -141 *

23 -56 -99 * 46 138 52

September 2003:

 Under 65 -65 -48 -18 18 61 -51

 65 and older

 Total

0

a

-284 * -58 -12 0 -354 **

-65 -332 ** -75 6 61 -405 *

Source: Mathematica Policy Research, from linked 2001 SIPP-MBR-PHUS records.

Note: The category "all other beneficiaries" includes spouses caring for minor children, widow(er)s caring

 for minor children, disabled widow(er)s, adults disabled in childhood, student children, minor children,

 and other individuals who have a current payment status and who are not elsewhere classified.

a

 Since the cross-sectional sample estimate is zero, the full panel estimate is zero as well.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

* Statistically significant at 0.10 level
 

 

 

 

 

 

TABLE 7

ENTRIES INTO AND EXITS FROM SOCIAL SECURITY BENEFICIARY CATEGORIES

BETWEEN JANUARY 2001 AND SEPTEMBER 2003

(Thousands of Persons)

Beneficiary January Entries into Exits from September

Category 2001 Category Category 2003

Wave 1 Sample with Wave 2 and Matched Data

Disabled worker 5,000 1,835 939 5,895

Retired worker 28,055 4,559 2,563 30,051

Aged non-widow 1,960 194 355 1,799

Aged widow 3,441 599 443 3,597

All other beneficiaries 4,007 1,330 1,168 4,169

Total 42,462 8,517 5,468 45,511

Difference between Full Panel Sample with Matched Data

and Wave 1 Sample with Wave 2 and Matched Data

Disabled worker 23 -35 52 -65

Retired worker -56 -86 190 ** -332 **

Aged non-widow -99 * -11 -34 -75

Aged widow 46 -13 27 6

All other beneficiaries 138 -104 -27 61

Total 52 -249 * 208 -405 *

Source: Mathematica Policy Research, from 2001 linked SIPP-MBR-PHUS records.

Note: The category "all other beneficiaries" includes spouses caring for minor children,

 widow(er)s caring for minor children, disabled widow(er)s, adults disabled in childhood,

 student children, minor children, and other individuals who have a current payment status

 and who are not elsewhere classified.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

 * Statistically significant at 0.10 level
 

 

 

TABLE 8

MEAN DOLLAR VALUES OF SELECTED PAYMENT VARIABLES AMONG RETIRED AND DISABLED WORKERS 

WHO ARE CURRENT BENEFICIARIES, JANUARY 2001 AND SEPTEMBER 2003

January 2001 September 2003

Retired Workers Retired Workers

Under Disabled Under Disabled

Payment Variable 65 65+ Total Workers 65 65+ Total Workers

Wave 1 Sample with Wave 2 and Matched Data

Family Maximum Benefit 1,628 1,467 1,482 1,116 1,703 1,481 1,502 1,158

Indexed Monthly Earnings 2,069 1,099 1,190 1,178 2,192 1,224 1,316 1,340

Monthly Benefit Amount 809 858 854 768 810 867 862 800

Monthly Benefit Payable 806 813 812 745 806 817 816 777

Medicare Part B Premium 1 45 41 22 2 49 45 23

Monthly Benefit Paid 732 810 802 717 755 813 807 816

Primary Insurance Amount 953 856 865 775 991 863 876 806

Social Security Income 733 855 843 739 757 862 852 838

Difference between Full Panel Sample with Matched Data and

Wave 1 Sample with Wave 2 and Matched Data

Family Maximum Benefit -1 -7 -6 -1 7 -10 -8 -9

Indexed Monthly Earnings -11 -13 -12 -8 12 -14 -12 -13

Monthly Benefit Amount -1 -4 -3 0 -2 -6 * -5 * -5

Monthly Benefit Payable -1 -3 -3 0 -2 -6 * -5 * -5

Medicare Part B Premium 0 0 0 0 0 0 0 0

Monthly Benefit Paid -5 -3 -3 17 -1 -6 * -5 * -4

Primary Insurance Amount -1 -5 -4 0 4 -6 * -5 * -5

Social Security Income -5 -3 -4 17 -1 -6 * -6 * -4

Source: Mathematica Policy Research, from 2001 linked SIPP-MBR-PHUS records.

 * Statistically significant at 0.10 level
TABLE 9

SSI RECIPIENTS IDENTIFIED IN THE SSR BY AGE AND ELIGIBILITY CATEGORY: JANUARY 2001 AND SEPTEMBER 2003

Month and Eligibility Age in Month

Category Under 18 18-24 25-49 50-61 62-65 65+ Total

Wave 1 Sample with Wave 2 and Matched Data

January 2001:

 Aged 0 0 0 0 4,783 1,095,341 1,100,124

 Blind 9,896 14,608 22,902 27,112 4,275 10,236 89,030

 Disabled 770,905 479,866 2,322,438 1,154,721 220,356 589,781 5,538,066

September 2003:

 Aged 0 0 0 0 0 1,123,836 1,123,836

 Blind 9,896 0 43,487 27,112 0 9,616 90,111

 Disabled 881,737 490,619 2,189,979 1,164,071 312,618 642,591 5,681,615

Difference between Full Panel Sample with Matched Data and

Wave 1 Sample with Wave 2 and Matched Data

January 2001:

 Aged 0

a a a a

0 0 0 1,136 101,561 102,698

 Blind 6,460 8,456 -8,495 -2,108 -4,275 3,573 3,612

 Disabled -63,302 47,503 102,339 73,048 801 -19,904 140,486

September 2003:

 Aged 0

a a a a a

0 0 0 0 135,306 135,306

 Blind 6,460 a a

0 -17,295 -2,108 0 -2,715 -15,659

 Disabled -76,053 -33,565 142,597 55,695 19,087 -5,821 101,941

Source: Mathematica Policy Research, from linked 2001 SIPP-SSR records.

a

 Since the cross-sectional sample estimate is zero, the full panel estimate is zero as well.
 

 

 

 

 

TABLE 10A

MEAN DOLLAR VALUES OF SELECTED PAYMENT VARIABLES ON THE SSR FOR SSI RECIPIENTS BY AGE,

JANUARY 2001 AND SEPTEMBER 2003

Age in Month

Month and Payment Variable Under 18 18-24 25-49 50-61 62-65 65+ Total

January 2001

 Earned Income

 Unearned Income

 Federal Money Amount Payment

 State Support Amount

Wave 1 Sample with Wave 2 and Matched Data

2 28 11 6 2 7 9

79 66 116 133 169 245 145

417 391 364 488 320 258 367

14 30 31 33 34 58 36

September 2003

 Earned Income

 Unearned Income

 Federal Money Amount Payment

 State Support Amount

0 23 8 2 0 3 6

63 40 140 135 224 240 151

469 465 382 361 280 256 359

25 23 45 46 39 76 48

Difference between Full Panel Sample with Matched Data and

Wave 1 Sample with Wave 2 and Matched Data

January 2001

 Earned Income

 Unearned Income

 Federal Money Amount Payment

 State Support Amount

1 0 3 2 *** -2 0 2

-7 -3 -14 * 5 23 -4 -4

6 27 25 * 31 -20 -2 15 *

2 2 -2 -1 1 1 0

September 2003

 Earned Income

 Unearned Income

 Federal Money Amount Payment

 State Support Amount

0 11 2 0 2 2*

-2 2 -13 5 -5 2 0

2 -11 9 -4 0 -2 -2

3 -3 -1 -2 4 7 * 2

0

a

Source: Mathematica Policy Research, from linked 2001 SIPP-SSR records.

a

 Since the cross-sectional sample estimate is zero, the full panel estimate is zero as well.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

* Statistically significant at 0.10 level
 

 

 

 

 

 

 

 

TABLE 10B

GROSS CHANGE IN PAYMENT VARIABLES ON THE SSR FILE, JANUARY 2001 THROUGH

SEPTEMBER 2003, FOR SSI RECIPIENTS BY AGE

Difference between Full Panel

Sample with Matched Data and 

Wave 1 Sample with Wave 2 Wave 1 Sample with Wave 2

and Matched Data and Matched Data

Age in January 2001 Age in January 2001 Payment Variable and 

Gross Change Under 65 65+ Total Under 65 65+ Total

Earned Income

 Positive Change 2.8 0.8 2.3 1.0 ** 0.4 0.9 **

 Negative Change 3.6 3.2 3.5 0.3 0.1 0.2

 No Change 93.6 96.0 94.2 -1.3 * -0.5 -1.1 *

Unearned Income

 Positive Change 11.9 6.1 10.5 -1.1 0.4 -0.7

 Negative Change 32.3 61.0 39.2 -1.2 1.6 -0.3

 No Change 55.8 32.9 50.3 2.2 -1.9 1.0

Federal Payment

 Positive Change 19.7 9.3 17.2 -2.7 ** 1.5 -1.7 *

 Negative Change 77.2 85.7 79.3 3.8 *** -2.1 2.4 **

 No Change 3.1 5.0 3.5 -1.2 * 0.6 -0.7

State Support Amount 

Positive Change 13.0 28.3 16.7 0.6 2.2 1.1

 Negative Change 19.9 17.0 19.2 0.2 0.0 0.1

 No Change 67.1 54.6 64.1 -0.8 -2.1 -1.2

Source: Mathematica Policy Research, from linked 2001 SIPP-SSR records.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

 * Statistically significant at 0.10 level
TABLE 11

DISTRIBUTION OF SSI PAYMENTS AS A PERCENTAGE OF PERSONAL INCOME AMONG PERSONS WITH POSITIVE SSI

AND POSITIVE TOTAL INCOME BY SELECTED PERSONAL CHARACTERISTICS

Difference between Full Panel Sample with

Matched Data and Wave 1 Sample with

Wave 1 Sample with Wave 2 and Matched Data

SSI Payment as a Percentage of

Wave 2 and Matched Data

SSI Payment as a Percentage of

Total Personal Income Total Personal Income

Characteristic 0-24% 25-49% 50-74% 75-99% 100% 0-24% 25-49% 50-74% 75-99% 100%

All Recipients 21.8 18.9 11.3 8.9 39.1 -1.1 

 

 

 

 

0.8 -1.2 -0.1 1.6

Sex

 Male 19.0 13.9 9.2 10.4 47.5 -2.5 * 0.9 -2.5 ** 1.3 2.8

 Female 23.5 22.2 12.6 7.9 33.7 0.0 1.1 -0.1 -1.2 0.2

Age

15-17 0.0 0.0 4.4 20.2 75.5 0.0 a

0.0 a0.9 -1.5 0.6

18-64 17.4 15.9 11.6 9.6 45.5 -0.7 0.3 -0.9 0.8 0.5

65+ 33.2 27.2 10.9 6.4 22.2 -2.0 

 

 

 

 

2.4 -2.0 -2.2 3.7 **

Race

 White 23.4 20.0 10.0 8.8 37.9 -2.4 ** 1.3 -1.3 0.1 2.4 *

 Black 20.0 18.1 12.1 8.7 41.0 2.3 * 0.0 -2.1 -0.3 0.1

 American Indian, Alaska Native 25.9 10.0 14.2 8.7 41.2 0.1 3.5 3.2 -1.2 -5.6

 Asian, Pacific Islander 12.5 16.6 18.6 11.0 41.3 -4.6 -0.1 1.8 -0.8 3.7

Ethnicity

 Hispanic 21.1 18.8 9.5 8.9 41.7 -2.4 3.9 *** -1.0 1.5 -2.0

 Non-Hispanic 21.9 19.0 11.8 8.9 38.4 -0.8 0.0 -1.2 -0.6 2.5 **

Marital Status

 Married 17.5 20.0 12.7 12.9 37.0 -1.4 

 

 

-0.4 -0.3 -0.3 2.4

 Widowed 35.1 22.3 11.0 5.7 25.9 2.5 0.4 0.4 -4.0 ** 0.7

 Divorced or separated 25.1 19.3 10.8 8.5 36.2 -1.1 1.9 -1.4 -0.9 1.5

 Never married 15.3 16.5 11.0 8.7 48.5 -2.0 * 1.1 -2.2 * 2.0 * 1.1

Source: Mathematica Policy Research, from linked 2001 SIPP-SSR records.

a

 Since the cross-sectional sample estimate is zero, the full panel estimate is zero as well.

*** Statistically significant at 0.01 level

 ** Statistically significant at 0.05 level

* Statistically significant at 0.10 level