65% is the change from 600 to 990
Calculation steps:
[( 990 - 600 ) ÷ 600] x 100 = 65%
Formula
Percentage change = [(990 - 600) / 600] x 100
Subtract the new number by the original number
990 - 600 = 390
390 ÷ 600 = 0.65
0.65 x 100 = 65%
Example