-97.64% is the change from 509 to 12
Calculation steps:
[( 12 - 509 ) ÷ 509] x 100 = -97.64%
Formula
Percentage change = [(12 - 509) / 509] x 100
Subtract the new number by the original number
12 - 509 = -497
-497 ÷ 509 = -0.9764243614931237
-0.9764243614931237 x 100 = -97.64%