years of schooling

[decipheringstata]

I am trying to calculate total years of schooling based on year highest level of education was attained and the year of birth. From that I would like to calculate total years of schooling as follows:
Year highest level of education was attained- year of birth- 4
say variable x= Year highest level of education was attained

y=year of birth
I'm trying the stata command
"generate yrschooling= x-y-4"
But that doesn't work as I'm getting numbers from -59 to 61. Any ideas what the correct command should be?

Thanks.

[Clyde Schechter]

I think you need to show us a representative sample of your data, as well as the exact code that you used. Please do that by -list-ing some observation and then pasting the output from the Results window into a code block here on the forum.