-39% is the change from 836 to 510
Calculation steps:
[( 510 - 836 ) ÷ 836] x 100 = -39%
Formula
Percentage change = [(510 - 836) / 836] x 100
Subtract the new number by the original number
510 - 836 = -326
-326 ÷ 836 = -0.38995215311004783
-0.38995215311004783 x 100 = -39%