Comparing CPI99 value of 2015 in IPUMS CPS and IPUMS ACS datasets

Hey Users,

I was looking through the CPI99 documentation in CPS and USAand noticed a discrepancy between the pages I don’t quite understand. In the CPS version of the page it appears that in order to adjust 2015 $ to 1999 levels we multiply by 0.703. However, in the USA version it seems that in order to achive the same conversion we should multiply by 0.690.

Values of CPI99 in 2016 CPS ASEC (reference period of income variables is last calendar year) and the ACS 2015 (ref. period last 12 months) are indeed 0.703 and 0.690 respectively.

Did I misunderstand something?

Your reply would be much appropriated.

Thank you very much for your help!

You are not misunderstanding. This is actually an error. The value for CPI99 in IPUMS USA for 2015 dollars should be 0.703, not 0.690. This error should be fixed with the next IPUMS USA data release. In the meantime, you can simply replace the values in the 2015 ACS sample.

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