-98.76% is the change from 645 to 8
Calculation steps:
[( 8 - 645 ) ÷ 645] x 100 = -98.76%
Formula
Percentage change = [(8 - 645) / 645] x 100
Subtract the new number by the original number
8 - 645 = -637
-637 ÷ 645 = -0.9875968992248062
-0.9875968992248062 x 100 = -98.76%