50% is the change from 620 to 930
Calculation steps:
[( 930 - 620 ) ÷ 620] x 100 = 50%
Formula
Percentage change = [(930 - 620) / 620] x 100
Subtract the new number by the original number
930 - 620 = 310
310 ÷ 620 = 0.5
0.5 x 100 = 50%
Example