171.2% is the change from 250 to 678
Calculation steps:
[( 678 - 250 ) ÷ 250] x 100 = 171.2%
Formula
Percentage change = [(678 - 250) / 250] x 100
Subtract the new number by the original number
678 - 250 = 428
428 ÷ 250 = 1.712
1.712 x 100 = 171.2%
Example