-93.16% is the change from 307 to 21
Calculation steps:
[( 21 - 307 ) ÷ 307] x 100 = -93.16%
Formula
Percentage change = [(21 - 307) / 307] x 100
Subtract the new number by the original number
21 - 307 = -286
-286 ÷ 307 = -0.9315960912052117
-0.9315960912052117 x 100 = -93.16%