-37.32% is the change from 493 to 309
Calculation steps:
[( 309 - 493 ) ÷ 493] x 100 = -37.32%
Formula
Percentage change = [(309 - 493) / 493] x 100
Subtract the new number by the original number
309 - 493 = -184
-184 ÷ 493 = -0.37322515212981744
-0.37322515212981744 x 100 = -37.32%