-50% is the change from 506 to 253
Calculation steps:
[( 253 - 506 ) ÷ 506] x 100 = -50%
Formula
Percentage change = [(253 - 506) / 506] x 100
Subtract the new number by the original number
253 - 506 = -253
-253 ÷ 506 = -0.5
-0.5 x 100 = -50%
Example