-86.79% is the change from 159 to 21
Calculation steps:
[( 21 - 159 ) ÷ 159] x 100 = -86.79%
Formula
Percentage change = [(21 - 159) / 159] x 100
Subtract the new number by the original number
21 - 159 = -138
-138 ÷ 159 = -0.8679245283018868
-0.8679245283018868 x 100 = -86.79%