-50% is the change from 22 to 11
Calculation steps:
[( 11 - 22 ) ÷ 22] x 100 = -50%
Formula
Percentage change = [(11 - 22) / 22] x 100
Subtract the new number by the original number
11 - 22 = -11
-11 ÷ 22 = -0.5
-0.5 x 100 = -50%
Example