# Household ID for decennial census data 1900-1940 (not IPUMS) does not seem unique

**URL:** <https://forum.ipums.org/t/household-id-for-decennial-census-data-1900-1940-not-ipums-does-not-seem-unique/994>\
**Category:** USA\
**Created:** [August 10, 2015, 5:53pm UTC](https://forum.ipums.org/t/household-id-for-decennial-census-data-1900-1940-not-ipums-does-not-seem-unique/994 "2015-08-10T17:53:00Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![peteknepper](https://avatars.discourse-cdn.com/v4/letter/p/c89c15/32.png) [@peteknepper](https://forum.ipums.org/u/peteknepper)\
**Post date:** [August 10, 2015, 5:53pm UTC](https://forum.ipums.org/t/household-id-for-decennial-census-data-1900-1940-not-ipums-does-not-seem-unique/994/1 "2015-08-10T17:53:00Z")

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I’m using census data for 1900, 1910, 1920, 1930, and 1940. The data is not from IPUMS, but I was wondering if anyone had any advice for a problem I ran into. The household id variable does not seem to be unique; multiple households are coded with the same numeric value. Does anyone have an idea why this might be, or how to get around this issue?

Thanks in advance!