-55.99% is the change from 309 to 136
Calculation steps:
[( 136 - 309 ) ÷ 309] x 100 = -55.99%
Formula
Percentage change = [(136 - 309) / 309] x 100
Subtract the new number by the original number
136 - 309 = -173
-173 ÷ 309 = -0.5598705501618123
-0.5598705501618123 x 100 = -55.99%