-97.71% is the change from 306 to 7
Calculation steps:
[( 7 - 306 ) ÷ 306] x 100 = -97.71%
Formula
Percentage change = [(7 - 306) / 306] x 100
Subtract the new number by the original number
7 - 306 = -299
-299 ÷ 306 = -0.9771241830065359
-0.9771241830065359 x 100 = -97.71%