This document outlines 8 steps to calculate a retirement number: 1) Determine current annual spending 2) Subtract rent/mortgage if paid off in retirement 3) Subtract life/disability insurance if not needed in retirement 4) Reduce food budget based on age 5) Reduce transportation budget based on age 6) Increase healthcare spending based on age 7) Subtract estimated social security benefits 8) Multiply final annual spending by 25 to get retirement number