-81.95% is the change from 820 to 148
Calculation steps:
[( 148 - 820 ) ÷ 820] x 100 = -81.95%
Formula
Percentage change = [(148 - 820) / 820] x 100
Subtract the new number by the original number
148 - 820 = -672
-672 ÷ 820 = -0.8195121951219512
-0.8195121951219512 x 100 = -81.95%