-3.94% is the change from 507 to 487
Calculation steps:
[( 487 - 507 ) ÷ 507] x 100 = -3.94%
Formula
Percentage change = [(487 - 507) / 507] x 100
Subtract the new number by the original number
487 - 507 = -20
-20 ÷ 507 = -0.03944773175542406
-0.03944773175542406 x 100 = -3.94%