-99.53% is the change from 645 to 3
Calculation steps:
[( 3 - 645 ) ÷ 645] x 100 = -99.53%
Formula
Percentage change = [(3 - 645) / 645] x 100
Subtract the new number by the original number
3 - 645 = -642
-642 ÷ 645 = -0.9953488372093023
-0.9953488372093023 x 100 = -99.53%