-92.24% is the change from 850 to 66
Calculation steps:
[( 66 - 850 ) ÷ 850] x 100 = -92.24%
Formula
Percentage change = [(66 - 850) / 850] x 100
Subtract the new number by the original number
66 - 850 = -784
-784 ÷ 850 = -0.9223529411764706
-0.9223529411764706 x 100 = -92.24%