-90.23% is the change from 307 to 30
Calculation steps:
[( 30 - 307 ) ÷ 307] x 100 = -90.23%
Formula
Percentage change = [(30 - 307) / 307] x 100
Subtract the new number by the original number
30 - 307 = -277
-277 ÷ 307 = -0.9022801302931596
-0.9022801302931596 x 100 = -90.23%