-49.32% is the change from 511 to 259
Calculation steps:
[( 259 - 511 ) ÷ 511] x 100 = -49.32%
Formula
Percentage change = [(259 - 511) / 511] x 100
Subtract the new number by the original number
259 - 511 = -252
-252 ÷ 511 = -0.4931506849315068
-0.4931506849315068 x 100 = -49.32%