-97.5% is the change from 519 to 13
Calculation steps:
[( 13 - 519 ) ÷ 519] x 100 = -97.5%
Formula
Percentage change = [(13 - 519) / 519] x 100
Subtract the new number by the original number
13 - 519 = -506
-506 ÷ 519 = -0.9749518304431599
-0.9749518304431599 x 100 = -97.5%