-62.24% is the change from 821 to 310
Calculation steps:
[( 310 - 821 ) ÷ 821] x 100 = -62.24%
Formula
Percentage change = [(310 - 821) / 821] x 100
Subtract the new number by the original number
310 - 821 = -511
-511 ÷ 821 = -0.6224116930572473
-0.6224116930572473 x 100 = -62.24%