-3.4% is the change from 911 to 880
Calculation steps:
[( 880 - 911 ) ÷ 911] x 100 = -3.4%
Formula
Percentage change = [(880 - 911) / 911] x 100
Subtract the new number by the original number
880 - 911 = -31
-31 ÷ 911 = -0.03402854006586169
-0.03402854006586169 x 100 = -3.4%