-1.21% is the change from 911 to 900
Calculation steps:
[( 900 - 911 ) ÷ 911] x 100 = -1.21%
Formula
Percentage change = [(900 - 911) / 911] x 100
Subtract the new number by the original number
900 - 911 = -11
-11 ÷ 911 = -0.012074643249176729
-0.012074643249176729 x 100 = -1.21%