-97.96% is the change from 637 to 13
Calculation steps:
[( 13 - 637 ) ÷ 637] x 100 = -97.96%
Formula
Percentage change = [(13 - 637) / 637] x 100
Subtract the new number by the original number
13 - 637 = -624
-624 ÷ 637 = -0.9795918367346939
-0.9795918367346939 x 100 = -97.96%