150% is the change from 308 to 770
Calculation steps:
[( 770 - 308 ) ÷ 308] x 100 = 150%
Formula
Percentage change = [(770 - 308) / 308] x 100
Subtract the new number by the original number
770 - 308 = 462
462 ÷ 308 = 1.5
1.5 x 100 = 150%
Example