-11% is the change from 900 to 801
Calculation steps:
[( 801 - 900 ) ÷ 900] x 100 = -11%
Formula
Percentage change = [(801 - 900) / 900] x 100
Subtract the new number by the original number
801 - 900 = -99
-99 ÷ 900 = -0.11
-0.11 x 100 = -11%
Example