-30.45% is the change from 509 to 354
Calculation steps:
[( 354 - 509 ) ÷ 509] x 100 = -30.45%
Formula
Percentage change = [(354 - 509) / 509] x 100
Subtract the new number by the original number
354 - 509 = -155
-155 ÷ 509 = -0.3045186640471513
-0.3045186640471513 x 100 = -30.45%
Example