-80% is the change from 515 to 103
Calculation steps:
[( 103 - 515 ) ÷ 515] x 100 = -80%
Formula
Percentage change = [(103 - 515) / 515] x 100
Subtract the new number by the original number
103 - 515 = -412
-412 ÷ 515 = -0.8
-0.8 x 100 = -80%
Example