-38.36% is the change from 511 to 315
Calculation steps:
[( 315 - 511 ) ÷ 511] x 100 = -38.36%
Formula
Percentage change = [(315 - 511) / 511] x 100
Subtract the new number by the original number
315 - 511 = -196
-196 ÷ 511 = -0.3835616438356164
-0.3835616438356164 x 100 = -38.36%