I heard that CPS ORG data starts from 1979
But when I check the hourly wage data in the outgoing rotation group of IPUMS CPS,
the variable starts from 1989 in yearly data, not monthly
May I know the reason that the hourly wage variable starts in 1989 in IPUMS CPS?
If I want to use the IPUMS CPS data (1989 - 2018) with the NBER CPS ORG (1979 - 1988) to increase the duration, Is there anything I should be aware of?