-81.41% is the change from 538 to 100
Calculation steps:
[( 100 - 538 ) ÷ 538] x 100 = -81.41%
Formula
Percentage change = [(100 - 538) / 538] x 100
Subtract the new number by the original number
100 - 538 = -438
-438 ÷ 538 = -0.8141263940520446
-0.8141263940520446 x 100 = -81.41%