Testing for a trend in the gender wage gap.

[Emanuele Zanon]

I have a dataset which contains information about many workers and their wages. Different workers are present in the dataset for different time periods.
I have already found that there is an income gap between female and male workers using a simple regression, and I corrected for many variables using dummies.
I am now asked to "construct and estimate a regression model that would test whether there is a trend in the gender gap". I assume that I need to use the command regress for income on gender, as before, but I don't know how to consider the time dimension, and the internet doesn't seem to have clear answers.
Thank you in advance.

[Carlo Lazzaro]

Emanuele:
as per your description (that, unfortunately, cannot replace sharing what you typed and what Stata gave you back, as per FAQ), you seem to have a panel dataset.
As your question seems related to a home/class assignment (please correct me if I'm wrong) that, as per FAQ again, should neither posted, nor answered on this forum, my advice is to take a look at -xtreg- (if your have a N>T panel dataset) or -xtregar- and -xtgls- if is the other way round.
In addition, you may want to type -search oaxaca- and see which entries fit with your research goals.