Automatically change output column headers based on month

I have looked at many topics, but cannot find what I am looking for. 

I want to change the header in the output to the current month automatically. I was *hoping* there would be a way to say "[ThisMonth] Sales" for one column header and "[ThisMonth]-1 Sales", so that it would spit out "November Sales" and "October Sales". I already have all of the data manipulation figured out, so I am focused just on the text of the header of a couple columns. 

I want to avoid having to manually change the output file headers every month. I hope I explained that adequately.

I appreciate any assistance you can provide!