159.38% is the change from 320 to 830
Calculation steps:
[( 830 - 320 ) ÷ 320] x 100 = 159.38%
Formula
Percentage change = [(830 - 320) / 320] x 100
Subtract the new number by the original number
830 - 320 = 510
510 ÷ 320 = 1.59375
1.59375 x 100 = 159.38%