-32.5% is the change from 957 to 646
Calculation steps:
[( 646 - 957 ) ÷ 957] x 100 = -32.5%
Formula
Percentage change = [(646 - 957) / 957] x 100
Subtract the new number by the original number
646 - 957 = -311
-311 ÷ 957 = -0.32497387669801464
-0.32497387669801464 x 100 = -32.5%