83.45% is the change from 284 to 521
Calculation steps:
[( 521 - 284 ) ÷ 284] x 100 = 83.45%
Formula
Percentage change = [(521 - 284) / 284] x 100
Subtract the new number by the original number
521 - 284 = 237
237 ÷ 284 = 0.8345070422535211
0.8345070422535211 x 100 = 83.45%