Social Security Public-Use Data Files (SSA)

Microdata from administrative sources like the Master Beneficiary Record, Supplemental Security Record.

Tables contain either one record per person or one record per person per year.
A systematic sample of either social security number holders (most americans) or program recipients (current beneficiaries). Multiply 1% samples by 100 to get weighted statistics, 5% samples by 20.
No expected release timeline.
Released by the Office of Research, Evaluation, and Statistics, US Social Security Administration.

Download, Import, Preparation

Download and import the 1951-2006 one percent files with one record per person and per person-year:

library(haven)
library(httr)

tf <- tempfile()

ssa_url <- "https://www.ssa.gov/policy/docs/microdata/epuf/epuf2006_sas_files.zip"

GET( ssa_url , write_disk( tf ) , progress() )

ssa_files <- unzip( tf , exdir = tempdir() )

ssa_fn <- grep( 'demographic' , ssa_files , value = TRUE )

annual_fn <- grep( 'annual' , ssa_files , value = TRUE )

ssa_tbl <- read_sas( ssa_fn )

annual_tbl <- read_sas( annual_fn )

ssa_df <- data.frame( ssa_tbl )

annual_df <- data.frame( annual_tbl )

names( ssa_df ) <- tolower( names( ssa_df ) )

names( annual_df ) <- tolower( names( annual_df ) )

Sum up 1951-1952 and 1953-2006 earnings, and also 1953-2006 credits, copying the naming convention:

summed_earnings_5152 <-
    with( 
        subset( annual_df , year_earn %in% 1951:1952 ) , 
        aggregate( annual_earnings , list( id ) , sum )
    )
    
names( summed_earnings_5152 ) <- c( 'id' , 'tot_cov_earn5152' )

summed_earnings_5306 <-
    with( 
        subset( annual_df , year_earn > 1952 ) , 
        aggregate( annual_earnings , list( id ) , sum )
    )
    
names( summed_earnings_5306 ) <- c( 'id' , 'tot_cov_earn5306' )

summed_quarters_5306 <-
    with( 
        subset( annual_df , year_earn > 1952 ) , 
        aggregate( annual_qtrs , list( id ) , sum )
    )

names( summed_quarters_5306 ) <- c( 'id' , 'qc5306' )

Isolate a single year of earnings:

earnings_2006 <- annual_df[ annual_df[ , 'year_earn' ] == 2006 , c( 'id' , 'annual_earnings' ) ]

names( earnings_2006 ) <- c( 'id' , 'tot_cov_earn06' )

Merge each new column on to the person-level table, then add zeroes to person-years without earnings:

stopifnot( all( !is.na( ssa_df ) ) )

before_nrow <- nrow( ssa_df )

ssa_df <- merge( ssa_df , summed_earnings_5152 , all.x = TRUE )

ssa_df <- merge( ssa_df , summed_earnings_5306 , all.x = TRUE )

ssa_df <- merge( ssa_df , summed_quarters_5306 , all.x = TRUE )

ssa_df <- merge( ssa_df , earnings_2006 , all.x = TRUE )

ssa_df[ is.na( ssa_df ) ] <- 0

stopifnot( nrow( ssa_df ) == before_nrow )

Save Locally

Save the object at any point:

# ssa_fn <- file.path( path.expand( "~" ) , "SSA" , "this_file.rds" )
# saveRDS( ssa_df , file = ssa_fn , compress = FALSE )

Load the same object:

# ssa_df <- readRDS( ssa_fn )

Variable Recoding

Add new columns to the data set:

ssa_df <- 
    transform( 
        ssa_df ,

        decade_of_birth = floor( yob / 10 ) * 10 ,
        
        sex = factor( sex , levels = 1:2 , labels = c( 'male' , 'female' ) ) ,
        
        tot_cov_earn3706 = ( tot_cov_earn3750 + tot_cov_earn5152 + tot_cov_earn5306 ) ,
        
        qc3706 = ( qc3750 + qc5152 + qc5306 ) ,
        
        any_earnings_2006 = ( tot_cov_earn06 > 0 ) ,
        
        earnings_periods =
            factor(
                ifelse( ( tot_cov_earn5152 + tot_cov_earn5306 > 0 ) & tot_cov_earn3750 > 0 , 1 ,
                ifelse( tot_cov_earn5152 > 0 | tot_cov_earn5306 > 0 , 2 ,
                ifelse( tot_cov_earn3750 > 0 , 3 , 4 ) ) ) ,
                levels = 1:4 ,
                labels =
                    c( 'Earnings in both periods' , 'Earnings during 1951-2006 only' ,
                        'Earnings during 1937-1950 only' , 'No earnings' ) )
    )

Analysis Examples with base R

Unweighted Counts

Count the unweighted number of records in the table, overall and by groups:

nrow( ssa_df )

table( ssa_df[ , "sex" ] , useNA = "always" )

Descriptive Statistics

Calculate the mean (average) of a linear variable, overall and by groups:

mean( ssa_df[ , "tot_cov_earn3706" ] )

tapply(
    ssa_df[ , "tot_cov_earn3706" ] ,
    ssa_df[ , "sex" ] ,
    mean 
)

Calculate the distribution of a categorical variable, overall and by groups:

prop.table( table( ssa_df[ , "decade_of_birth" ] ) )

prop.table(
    table( ssa_df[ , c( "decade_of_birth" , "sex" ) ] ) ,
    margin = 2
)

Calculate the sum of a linear variable, overall and by groups:

sum( ssa_df[ , "tot_cov_earn3706" ] )

tapply(
    ssa_df[ , "tot_cov_earn3706" ] ,
    ssa_df[ , "sex" ] ,
    sum 
)

Calculate the median (50th percentile) of a linear variable, overall and by groups:

quantile( ssa_df[ , "tot_cov_earn3706" ] , 0.5 )

tapply(
    ssa_df[ , "tot_cov_earn3706" ] ,
    ssa_df[ , "sex" ] ,
    quantile ,
    0.5 
)

Subsetting

Limit your data.frame to individuals with at least forty lifetime credits:

sub_ssa_df <- subset( ssa_df , qc3706 >= 40 )

Calculate the mean (average) of this subset:

mean( sub_ssa_df[ , "tot_cov_earn3706" ] )

Measures of Uncertainty

Calculate the variance, overall and by groups:

var( ssa_df[ , "tot_cov_earn3706" ] )

tapply(
    ssa_df[ , "tot_cov_earn3706" ] ,
    ssa_df[ , "sex" ] ,
    var 
)

Regression Models and Tests of Association

Perform a t-test:

t.test( tot_cov_earn3706 ~ any_earnings_2006 , ssa_df )

Perform a chi-squared test of association:

this_table <- table( ssa_df[ , c( "any_earnings_2006" , "decade_of_birth" ) ] )

chisq.test( this_table )

Perform a generalized linear model:

glm_result <- 
    glm( 
        tot_cov_earn3706 ~ any_earnings_2006 + decade_of_birth , 
        data = ssa_df
    )

summary( glm_result )

Replication Example

This example matches statistics in The 2006 Earnings Public-Use Microdata File: An Introduction:

Chart 5. Percentage distribution of individuals in EPUF, by capped Social Security taxable earnings status:

chart_five_results <- prop.table( table( ssa_df[ , 'earnings_periods' ] ) )
chart_five_results <- round( 100 * chart_five_results )

stopifnot( chart_five_results[ 'Earnings in both periods' ] == 16 )
stopifnot( chart_five_results[ 'Earnings during 1951-2006 only' ] == 55 )
stopifnot( chart_five_results[ 'Earnings during 1937-1950 only' ] == 4 )
stopifnot( chart_five_results[ 'No earnings' ] == 25 )

Table 4. Average and median Social Security taxable earnings in EPUF, by sex, 1951–2006 (in dollars):

nonzero_2006_earners <- ssa_df[ ssa_df[ , 'tot_cov_earn06' ] > 0 , 'tot_cov_earn06' ]
stopifnot( round( mean( nonzero_2006_earners ) , 0 ) == 30953 )
stopifnot( round( quantile( nonzero_2006_earners )[ 3 ] , 0 ) == 24000 )

Table A1. Number and percentage distribution of individuals with Social Security taxable earnings records in EPUF, by sex, 1951–2006:

nonzero_2006_earners <- ssa_df[ ssa_df[ , 'tot_cov_earn06' ] > 0 , ]
stopifnot( round( mean( nonzero_2006_earners[ , 'tot_cov_earn06' ] ) , 0 ) == 30953 )
stopifnot( round( quantile( nonzero_2006_earners[ , 'tot_cov_earn06' ] )[ 3 ] , 0 ) == 24000 )

This example matches statistics in Comparing Earnings Estimates from the 2006 Earnings Public-Use File and the Annual Statistical Supplement:

Table 4. Comparing Supplement and EPUF estimates: Number of all, male, and female workers with any earnings during the year, 1951–2006:

stopifnot( round( nrow( nonzero_2006_earners ) * 100 , -3 ) == 156280000 )
earners_in_2006_by_sex <- table( nonzero_2006_earners[ , 'sex' ] ) * 100
stopifnot( round( earners_in_2006_by_sex[ 'male' ] , -3 ) == 81576000 )
stopifnot( round( earners_in_2006_by_sex[ 'female' ] , -3 ) == 74681000 )

Analysis Examples with `dplyr`

The R dplyr library offers an alternative grammar of data manipulation to base R and SQL syntax. dplyr offers many verbs, such as summarize, group_by, and mutate, the convenience of pipe-able functions, and the tidyverse style of non-standard evaluation. This vignette details the available features. As a starting point for SSA users, this code replicates previously-presented examples:

library(dplyr)
ssa_tbl <- as_tibble( ssa_df )

Calculate the mean (average) of a linear variable, overall and by groups:

ssa_tbl %>%
    summarize( mean = mean( tot_cov_earn3706 ) )

ssa_tbl %>%
    group_by( sex ) %>%
    summarize( mean = mean( tot_cov_earn3706 ) )

Analysis Examples with `data.table`

The R data.table library provides a high-performance version of base R’s data.frame with syntax and feature enhancements for ease of use, convenience and programming speed. data.table offers concise syntax: fast to type, fast to read, fast speed, memory efficiency, a careful API lifecycle management, an active community, and a rich set of features. This vignette details the available features. As a starting point for SSA users, this code replicates previously-presented examples:

library(data.table)
ssa_dt <- data.table( ssa_df )

Calculate the mean (average) of a linear variable, overall and by groups:

ssa_dt[ , mean( tot_cov_earn3706 ) ]

ssa_dt[ , mean( tot_cov_earn3706 ) , by = sex ]

Analysis Examples with `duckdb`

The R duckdb library provides an embedded analytical data management system with support for the Structured Query Language (SQL). duckdb offers a simple, feature-rich, fast, and free SQL OLAP management system. This vignette details the available features. As a starting point for SSA users, this code replicates previously-presented examples:

library(duckdb)
con <- dbConnect( duckdb::duckdb() , dbdir = 'my-db.duckdb' )
dbWriteTable( con , 'ssa' , ssa_df )

Calculate the mean (average) of a linear variable, overall and by groups:

dbGetQuery( con , 'SELECT AVG( tot_cov_earn3706 ) FROM ssa' )

dbGetQuery(
    con ,
    'SELECT
        sex ,
        AVG( tot_cov_earn3706 )
    FROM
        ssa
    GROUP BY
        sex'
)

Social Security Public-Use Data Files (SSA)

Recommended Reading

Download, Import, Preparation

Save Locally

Variable Recoding

Analysis Examples with base R

Unweighted Counts

Descriptive Statistics

Subsetting

Measures of Uncertainty

Regression Models and Tests of Association

Replication Example

Analysis Examples with dplyr

Analysis Examples with data.table

Analysis Examples with duckdb

Analysis Examples with `dplyr`

Analysis Examples with `data.table`

Analysis Examples with `duckdb`