-9.51% is the change from 820 to 742
Calculation steps:
[( 742 - 820 ) ÷ 820] x 100 = -9.51%
Formula
Percentage change = [(742 - 820) / 820] x 100
Subtract the new number by the original number
742 - 820 = -78
-78 ÷ 820 = -0.0951219512195122
-0.0951219512195122 x 100 = -9.51%