-1.55% is the change from 515 to 507
Calculation steps:
[( 507 - 515 ) ÷ 515] x 100 = -1.55%
Formula
Percentage change = [(507 - 515) / 515] x 100
Subtract the new number by the original number
507 - 515 = -8
-8 ÷ 515 = -0.015533980582524271
-0.015533980582524271 x 100 = -1.55%