-31.13% is the change from 938 to 646
Calculation steps:
[( 646 - 938 ) ÷ 938] x 100 = -31.13%
Formula
Percentage change = [(646 - 938) / 938] x 100
Subtract the new number by the original number
646 - 938 = -292
-292 ÷ 938 = -0.31130063965884863
-0.31130063965884863 x 100 = -31.13%