How to sum filtered results?

I have a spreadsheet from my HSA. I filtered the content to see just my payroll deductions that exist in one column then attempted to print it out thinking the data at the bottom of the window Sum would print as well. It didn't. Then I went about creating a row underneath to total the columns that are showing and the number is incorrect for the filtered data.

Reading in this forum I see that is as intended. Why would I bother filtering content to then run calculations on the unfiltered content?

Sorry for my tone but 1 hour of time wasted to get a sum of filtered content. Next time I'll just use a calculator and write it in.

I suppose it's counterintuitive because the Sum at the bottom of the window seems to understand my intention but there is not easy way to access that or print that out.

Is there a way to export just the filtered rows to another spreadsheet and then sum it there?