-21.36% is the change from 220 to 173
Calculation steps:
[( 173 - 220 ) ÷ 220] x 100 = -21.36%
Formula
Percentage change = [(173 - 220) / 220] x 100
Subtract the new number by the original number
173 - 220 = -47
-47 ÷ 220 = -0.21363636363636362
-0.21363636363636362 x 100 = -21.36%