(sub)totals location at bottom of invoice PDF

Hi,

Playing around with invoice plane, I noticed when generating the pdf, the (sub)totals are located directly under the last item line. Would it be possible to have (sub)total and tax part always at the bottom of the page (above the footer). I am still trying to find my way to the templates, so I might be an easy fix I can do self in php/css, but need a bit of guidance.

Thanks