-97.76% is the change from 936 to 21
Calculation steps:
[( 21 - 936 ) ÷ 936] x 100 = -97.76%
Formula
Percentage change = [(21 - 936) / 936] x 100
Subtract the new number by the original number
21 - 936 = -915
-915 ÷ 936 = -0.9775641025641025
-0.9775641025641025 x 100 = -97.76%