-51.25% is the change from 999 to 487
Calculation steps:
[( 487 - 999 ) ÷ 999] x 100 = -51.25%
Formula
Percentage change = [(487 - 999) / 999] x 100
Subtract the new number by the original number
487 - 999 = -512
-512 ÷ 999 = -0.5125125125125125
-0.5125125125125125 x 100 = -51.25%