-40.25% is the change from 815 to 487
Calculation steps:
[( 487 - 815 ) ÷ 815] x 100 = -40.25%
Formula
Percentage change = [(487 - 815) / 815] x 100
Subtract the new number by the original number
487 - 815 = -328
-328 ÷ 815 = -0.40245398773006136
-0.40245398773006136 x 100 = -40.25%