Trying to use OCC1990 for 1970, but extract only shows 84 (!?) observations for this variable. Can this be true?
I created an extract of my own and I found over 2 million responses for OCC1990 using the 1970 Form 2 Metro sample. I looked into your data extracts and the most recent extract containing 1970 data is from February of this year. Nothing in this extract looks as though it would cause the problem you are describing. It is possible that the file was not fully decompressed before being read into your statistical software. I would recommend resubmitting your extract, downloading it, and then decompressing it fully. If you are still having problems after reading the new data file into your statistical package, please respond to this forum post with an update.
I hope this helps.
Excellent–thanks so much!