-37.94% is the change from 817 to 507
Calculation steps:
[( 507 - 817 ) ÷ 817] x 100 = -37.94%
Formula
Percentage change = [(507 - 817) / 817] x 100
Subtract the new number by the original number
507 - 817 = -310
-310 ÷ 817 = -0.379436964504284
-0.379436964504284 x 100 = -37.94%