-49.84% is the change from 620 to 311
Calculation steps:
[( 311 - 620 ) ÷ 620] x 100 = -49.84%
Formula
Percentage change = [(311 - 620) / 620] x 100
Subtract the new number by the original number
311 - 620 = -309
-309 ÷ 620 = -0.49838709677419357
-0.49838709677419357 x 100 = -49.84%