-31.45% is the change from 938 to 643
Calculation steps:
[( 643 - 938 ) ÷ 938] x 100 = -31.45%
Formula
Percentage change = [(643 - 938) / 938] x 100
Subtract the new number by the original number
643 - 938 = -295
-295 ÷ 938 = -0.31449893390191896
-0.31449893390191896 x 100 = -31.45%