-37.87% is the change from 816 to 507
Calculation steps:
[( 507 - 816 ) ÷ 816] x 100 = -37.87%
Formula
Percentage change = [(507 - 816) / 816] x 100
Subtract the new number by the original number
507 - 816 = -309
-309 ÷ 816 = -0.3786764705882353
-0.3786764705882353 x 100 = -37.87%