421% is the change from 100 to 521
Calculation steps:
[( 521 - 100 ) ÷ 100] x 100 = 421%
Formula
Percentage change = [(521 - 100) / 100] x 100
Subtract the new number by the original number
521 - 100 = 421
421 ÷ 100 = 4.21
4.21 x 100 = 421%
Example