-57.08% is the change from 911 to 391
Calculation steps:
[( 391 - 911 ) ÷ 911] x 100 = -57.08%
Formula
Percentage change = [(391 - 911) / 911] x 100
Subtract the new number by the original number
391 - 911 = -520
-520 ÷ 911 = -0.570801317233809
-0.570801317233809 x 100 = -57.08%