-36.15% is the change from 816 to 521
Calculation steps:
[( 521 - 816 ) ÷ 816] x 100 = -36.15%
Formula
Percentage change = [(521 - 816) / 816] x 100
Subtract the new number by the original number
521 - 816 = -295
-295 ÷ 816 = -0.36151960784313725
-0.36151960784313725 x 100 = -36.15%