-66% is the change from 250 to 85
Calculation steps:
[( 85 - 250 ) ÷ 250] x 100 = -66%
Formula
Percentage change = [(85 - 250) / 250] x 100
Subtract the new number by the original number
85 - 250 = -165
-165 ÷ 250 = -0.66
-0.66 x 100 = -66%
Example