-40% is the change from 315 to 189
Calculation steps:
[( 189 - 315 ) ÷ 315] x 100 = -40%
Formula
Percentage change = [(189 - 315) / 315] x 100
Subtract the new number by the original number
189 - 315 = -126
-126 ÷ 315 = -0.4
-0.4 x 100 = -40%
Example