-80.12% is the change from 503 to 100
Calculation steps:
[( 100 - 503 ) ÷ 503] x 100 = -80.12%
Formula
Percentage change = [(100 - 503) / 503] x 100
Subtract the new number by the original number
100 - 503 = -403
-403 ÷ 503 = -0.8011928429423459
-0.8011928429423459 x 100 = -80.12%