-62.56% is the change from 820 to 307
Calculation steps:
[( 307 - 820 ) ÷ 820] x 100 = -62.56%
Formula
Percentage change = [(307 - 820) / 820] x 100
Subtract the new number by the original number
307 - 820 = -513
-513 ÷ 820 = -0.625609756097561
-0.625609756097561 x 100 = -62.56%