1200% is the change from 21 to 273
Calculation steps:
[( 273 - 21 ) ÷ 21] x 100 = 1200%
Formula
Percentage change = [(273 - 21) / 21] x 100
Subtract the new number by the original number
273 - 21 = 252
252 ÷ 21 = 12
12 x 100 = 1200%
Example