21.05% is the change from 285 to 345
Calculation steps:
[( 345 - 285 ) ÷ 285] x 100 = 21.05%
Formula
Percentage change = [(345 - 285) / 285] x 100
Subtract the new number by the original number
345 - 285 = 60
60 ÷ 285 = 0.21052631578947367
0.21052631578947367 x 100 = 21.05%