-52.86% is the change from 821 to 387
Calculation steps:
[( 387 - 821 ) ÷ 821] x 100 = -52.86%
Formula
Percentage change = [(387 - 821) / 821] x 100
Subtract the new number by the original number
387 - 821 = -434
-434 ÷ 821 = -0.5286236297198539
-0.5286236297198539 x 100 = -52.86%