-91.88% is the change from 813 to 66
Calculation steps:
[( 66 - 813 ) ÷ 813] x 100 = -91.88%
Formula
Percentage change = [(66 - 813) / 813] x 100
Subtract the new number by the original number
66 - 813 = -747
-747 ÷ 813 = -0.9188191881918819
-0.9188191881918819 x 100 = -91.88%