-22.57% is the change from 824 to 638
Calculation steps:
[( 638 - 824 ) ÷ 824] x 100 = -22.57%
Formula
Percentage change = [(638 - 824) / 824] x 100
Subtract the new number by the original number
638 - 824 = -186
-186 ÷ 824 = -0.22572815533980584
-0.22572815533980584 x 100 = -22.57%