19.07% is the change from 645 to 768
Calculation steps:
[( 768 - 645 ) ÷ 645] x 100 = 19.07%
Formula
Percentage change = [(768 - 645) / 645] x 100
Subtract the new number by the original number
768 - 645 = 123
123 ÷ 645 = 0.19069767441860466
0.19069767441860466 x 100 = 19.07%