The Benefits and Earnings Public-Use File, 2004, consists of two separate but linkable subfiles—one with benefit information and the other with longitudinal earnings information. Sample beneficiary records drawn from the Old-Age, Survivors, and Disability Insurance (OASDI) program can be linked to their corresponding earnings histories.

Information about beneficiaries needed to administer the OASDI program resides on SSA's Master Beneficiary Record (MBR) file, which in December 2004 contained records for approximately 47 million individuals who were entitled to receive an OASDI benefit for that month. Data in the benefit subfile are an extract from the MBR, consisting of a 1 percent random, representative sample of approximately 470,000 records. These records are representative of OASDI beneficiaries who were entitled to receive an OASDI benefit payment for December 2004. Each record in the benefit and earnings subfiles has a unique identifier that allows each earnings record to be linked to its appropriate benefit record. Both subfiles are available as flat text files or SAS data sets.

Since the sample for this public-use file is a representative, 1 percent random sample of persons entitled to receive an OASDI benefit payment for December 2004, all records have weight equal to 100. Variances and standard errors can be approximated with the standard formulas used for simple random sampling.

Descriptions of data fields are provided in the Data Dictionary for this file. The descriptions cover the content of each field, the method of presentation, and the disclosure avoidance steps taken to provide confidentiality. Because information on the internal MBR file is used to administer the OASDI program, these data are validated and kept current. As a result, the quality of the data in this public-use file is extremely high. Note that benefits payable for December 2004 are computed using earnings through the year 2003.

Individual identifiers have been removed from all records on this file, and other distinguishing characteristics have been modified to prevent identification of persons to whom a record pertains. Records are sequenced in random order.

Topcodes and bottomcodes are employed for all numeric fields to avoid showing extreme field values on a data record. Values beyond the topcode or bottomcode are replaced by the average of the values in excess of the respective topcode or bottomcode. Topcode and bottomcode values were derived at the national level, and the replacement values are also based on national estimates for this file. Values shown for categorical fields are groupings of detailed information from the internal file and numeric variables are random rounded. All topcode and bottomcode values, replacement values, and information on detailed groupings are provided to users as part of the file documentation.