-77.53% is the change from 850 to 191
Calculation steps:
[( 191 - 850 ) ÷ 850] x 100 = -77.53%
Formula
Percentage change = [(191 - 850) / 850] x 100
Subtract the new number by the original number
191 - 850 = -659
-659 ÷ 850 = -0.7752941176470588
-0.7752941176470588 x 100 = -77.53%