-42.86% is the change from 910 to 520
Calculation steps:
[( 520 - 910 ) ÷ 910] x 100 = -42.86%
Formula
Percentage change = [(520 - 910) / 910] x 100
Subtract the new number by the original number
520 - 910 = -390
-390 ÷ 910 = -0.42857142857142855
-0.42857142857142855 x 100 = -42.86%