-90.44% is the change from 638 to 61
Calculation steps:
[( 61 - 638 ) ÷ 638] x 100 = -90.44%
Formula
Percentage change = [(61 - 638) / 638] x 100
Subtract the new number by the original number
61 - 638 = -577
-577 ÷ 638 = -0.9043887147335423
-0.9043887147335423 x 100 = -90.44%