Description

BIRTHYR reports the person's year of birth. Researchers should use this variable with caution; see the comparability section for details.

BIRTHYR is a 4-digit numeric code reporting the respondent's year of birth. BIRTHYR specific variable codes for missing, edited, or unidentified observations, observations not applicable (N/A), observations not in universe (NIU), top and bottom value coding, etc. are provided below by Census year (and data sample if specified).

User Note: Researchers should use this variable with caution (See Comparability)

BIRTHYR Specific Variable Codes
9996 = not classified
9997 = illegible
9998 = unknown
9999 = missing/blank

Comparability

Self-reported birth year is available only for the 1 percent samples for 1900 and 1910, as well as the 1900 100% database - in which it occasionally conflicts with self-reported AGE. IPUMS retains this original detail; users should exercise caution in these situations.

In all other samples, self-reported birth year is not available but has been calculated by subtracting AGE from the survey year (MULTYEAR in the multi-year ACS/PRCS samples; YEAR in all other samples). For all respondents in the 1960-1980 samples, and for people under age 1 in 1870, 1880 (excluding the 100% database), and 1950 samples this is further refined using Birth quarter (BIRTHQTR). Where no additional information on the date of birth is available, it will be off by one year for everyone who has a birthday after the survey date, as seen in the following table:

BIRTHQTR is also available in the 2005-onward ACS/PRCS; however, since the date of survey is not fixed as it is for the decennial censuses, the true year of birth cannot be determined. Because ACS/PRCS respondents are surveyed throughout the year, though, the errors averaged across the entire sample will be close to zero.

Universe

Availability

• 2023: All samples
• 2022: All samples
• 2021: All samples
• 2020: All samples
• 2019: All samples
• 2018: All samples
• 2017: All samples
• 2016: All samples
• 2015: All samples
• 2014: All samples
• 2013: All samples
• 2012: All samples
• 2011: All samples
• 2010: ACS; ACS 3yr; ACS 5yr
• 2009: All samples
• 2008: All samples
• 2007: All samples
• 2006: All samples
• 2005: All samples
• 2004: All samples
• 2003: All samples
• 2002: All samples
• 2001: All samples
• 2000: All samples
• 1990: All samples
• 1980: All samples
• 1970: All samples
• 1960: All samples
• 1950: All samples
• 1940: All samples
• 1930: All samples
• 1920: All samples
• 1910: All samples
• 1900: All samples
• 1880: All samples
• 1870: All samples
• 1860: All samples
• 1850: All samples

• 2023: All samples
• 2022: All samples
• 2021: All samples
• 2020: All samples
• 2019: All samples
• 2018: All samples
• 2017: All samples
• 2016: All samples
• 2015: All samples
• 2014: All samples
• 2013: All samples
• 2012: All samples
• 2011: All samples
• 2010: PRCS; PRCS 3yr; PRCS 5yr
• 2009: All samples
• 2008: All samples
• 2007: All samples
• 2006: All samples
• 2005: All samples
• 2000: All samples
• 1990: All samples
• 1980: All samples
• 1970: All samples
• 1930: All samples
• 1920: All samples
• 1910: --

Flags

Editing Procedure

There is no editing procedure available for this variable.