-2.19% is the change from 957 to 936
Calculation steps:
[( 936 - 957 ) ÷ 957] x 100 = -2.19%
Formula
Percentage change = [(936 - 957) / 957] x 100
Subtract the new number by the original number
936 - 957 = -21
-21 ÷ 957 = -0.0219435736677116
-0.0219435736677116 x 100 = -2.19%