-61.95% is the change from 820 to 312
Calculation steps:
[( 312 - 820 ) ÷ 820] x 100 = -61.95%
Formula
Percentage change = [(312 - 820) / 820] x 100
Subtract the new number by the original number
312 - 820 = -508
-508 ÷ 820 = -0.6195121951219512
-0.6195121951219512 x 100 = -61.95%