-96.76% is the change from 309 to 10
Calculation steps:
[( 10 - 309 ) ÷ 309] x 100 = -96.76%
Formula
Percentage change = [(10 - 309) / 309] x 100
Subtract the new number by the original number
10 - 309 = -299
-299 ÷ 309 = -0.9676375404530745
-0.9676375404530745 x 100 = -96.76%