-31.05% is the change from 921 to 635
Calculation steps:
[( 635 - 921 ) ÷ 921] x 100 = -31.05%
Formula
Percentage change = [(635 - 921) / 921] x 100
Subtract the new number by the original number
635 - 921 = -286
-286 ÷ 921 = -0.31053203040173727
-0.31053203040173727 x 100 = -31.05%