-66.8% is the change from 250 to 83
Calculation steps:
[( 83 - 250 ) ÷ 250] x 100 = -66.8%
Formula
Percentage change = [(83 - 250) / 250] x 100
Subtract the new number by the original number
83 - 250 = -167
-167 ÷ 250 = -0.668
-0.668 x 100 = -66.8%
Example