-12.32% is the change from 138 to 121
Calculation steps:
[( 121 - 138 ) ÷ 138] x 100 = -12.32%
Formula
Percentage change = [(121 - 138) / 138] x 100
Subtract the new number by the original number
121 - 138 = -17
-17 ÷ 138 = -0.12318840579710146
-0.12318840579710146 x 100 = -12.32%