-37.07% is the change from 491 to 309
Calculation steps:
[( 309 - 491 ) ÷ 491] x 100 = -37.07%
Formula
Percentage change = [(309 - 491) / 491] x 100
Subtract the new number by the original number
309 - 491 = -182
-182 ÷ 491 = -0.37067209775967414
-0.37067209775967414 x 100 = -37.07%