-1.81% is the change from 938 to 921
Calculation steps:
[( 921 - 938 ) ÷ 938] x 100 = -1.81%
Formula
Percentage change = [(921 - 938) / 938] x 100
Subtract the new number by the original number
921 - 938 = -17
-17 ÷ 938 = -0.01812366737739872
-0.01812366737739872 x 100 = -1.81%