-28.75% is the change from 80 to 57
Calculation steps:
[( 57 - 80 ) ÷ 80] x 100 = -28.75%
Formula
Percentage change = [(57 - 80) / 80] x 100
Subtract the new number by the original number
57 - 80 = -23
-23 ÷ 80 = -0.2875
-0.2875 x 100 = -28.75%
Example