-36.91% is the change from 821 to 518
Calculation steps:
[( 518 - 821 ) ÷ 821] x 100 = -36.91%
Formula
Percentage change = [(518 - 821) / 821] x 100
Subtract the new number by the original number
518 - 821 = -303
-303 ÷ 821 = -0.3690621193666261
-0.3690621193666261 x 100 = -36.91%