-71.43% is the change from 28 to 8
Calculation steps:
[( 8 - 28 ) ÷ 28] x 100 = -71.43%
Formula
Percentage change = [(8 - 28) / 28] x 100
Subtract the new number by the original number
8 - 28 = -20
-20 ÷ 28 = -0.7142857142857143
-0.7142857142857143 x 100 = -71.43%