pre 1990 and post 1993
There are a couple ways to go about this. You’ve categorized this question under IPUMS USA, so I’ll address IPUMS USA first. IPUMS CPS provides the data used for officially calculating the unemployment rate in the US, so you might want to give this data a look.
In IPUMS USA, you’ll want to use the EMPSTAT variable. This variable indicates whether an individual was part of the labor force, and if so, whether the person was currently employed. You can then use the INDvariable to identify the various industries in which individuals work. Importantly, for the IND variable, if an individual is currently unemployed then the questionnaire asks for their most recent industry of employment. One limitation with IPUMS USA is the available sample years. The annual ACS data only start in the year 2000. This suggests your best bet may be to use IPUMS CPS.
In IPUMS CPS, you’ll want to use the variables with the same names, EMPSTAT and IND. The same details from IPUMS USA apply. The real benefit with IPUMS CPS is this survey has been administered annually, and even monthly, for at least the last 40 years.