-91.98% is the change from 823 to 66
Calculation steps:
[( 66 - 823 ) ÷ 823] x 100 = -91.98%
Formula
Percentage change = [(66 - 823) / 823] x 100
Subtract the new number by the original number
66 - 823 = -757
-757 ÷ 823 = -0.9198055893074119
-0.9198055893074119 x 100 = -91.98%