-83.56% is the change from 815 to 134
Calculation steps:
[( 134 - 815 ) ÷ 815] x 100 = -83.56%
Formula
Percentage change = [(134 - 815) / 815] x 100
Subtract the new number by the original number
134 - 815 = -681
-681 ÷ 815 = -0.8355828220858895
-0.8355828220858895 x 100 = -83.56%