Need to create a button to copy the current record details and update a couple of field labels

Hmm, I'am trying to minimize the amount of manual data entry for copying or updating these contract budget totals from year to year. We are currently using these fields to determine the increase or decrease from the previous contract to the current contract. 
So the FY17 Field represents the Total Cost for FY17 and the FY18 Total Cost shows what is the current spend. I have a formula field that determines the percent of increase or decrease from year to year.