2.73% is the change from 660 to 678
Calculation steps:
[( 678 - 660 ) ÷ 660] x 100 = 2.73%
Formula
Percentage change = [(678 - 660) / 660] x 100
Subtract the new number by the original number
678 - 660 = 18
18 ÷ 660 = 0.02727272727272727
0.02727272727272727 x 100 = 2.73%