-49.25% is the change from 999 to 507
Calculation steps:
[( 507 - 999 ) ÷ 999] x 100 = -49.25%
Formula
Percentage change = [(507 - 999) / 999] x 100
Subtract the new number by the original number
507 - 999 = -492
-492 ÷ 999 = -0.4924924924924925
-0.4924924924924925 x 100 = -49.25%