-81.84% is the change from 815 to 148
Calculation steps:
[( 148 - 815 ) ÷ 815] x 100 = -81.84%
Formula
Percentage change = [(148 - 815) / 815] x 100
Subtract the new number by the original number
148 - 815 = -667
-667 ÷ 815 = -0.8184049079754602
-0.8184049079754602 x 100 = -81.84%