-52.1% is the change from 309 to 148
Calculation steps:
[( 148 - 309 ) ÷ 309] x 100 = -52.1%
Formula
Percentage change = [(148 - 309) / 309] x 100
Subtract the new number by the original number
148 - 309 = -161
-161 ÷ 309 = -0.5210355987055016
-0.5210355987055016 x 100 = -52.1%