311.76% is the change from 102 to 420
Calculation steps:
[( 420 - 102 ) ÷ 102] x 100 = 311.76%
Formula
Percentage change = [(420 - 102) / 102] x 100
Subtract the new number by the original number
420 - 102 = 318
318 ÷ 102 = 3.1176470588235294
3.1176470588235294 x 100 = 311.76%