100% is the change from 331 to 662
Calculation steps:
[( 662 - 331 ) ÷ 331] x 100 = 100%
Formula
Percentage change = [(662 - 331) / 331] x 100
Subtract the new number by the original number
662 - 331 = 331
331 ÷ 331 = 1
1 x 100 = 100%
Example