-1.09% is the change from 921 to 911
Calculation steps:
[( 911 - 921 ) ÷ 921] x 100 = -1.09%
Formula
Percentage change = [(911 - 921) / 921] x 100
Subtract the new number by the original number
911 - 921 = -10
-10 ÷ 921 = -0.010857763300760043
-0.010857763300760043 x 100 = -1.09%