Urgent help- statistically significant mean differences

My task is to Test whether there are statistically significant mean differences in the log returns between the y stock and the S&P. The data for which is attached.

I have to do all of the analysis in Stata.

The data is not normal so I need to do a non-parametric test, I think a Ranksum or a kwallis in Stata?

How do I interpret these tests. Or what is the correct test.

Please help, it's due tomorrow


Less is more. Stay pure. Stay poor.
Not a fan of opening online files, but have you looked at the residual errors? Do you really know you can't use a ttest? What is the sample sizes? You can tranform data as well, correct?