3.78% is the change from 556 to 577
Calculation steps:
[( 577 - 556 ) ÷ 556] x 100 = 3.78%
Formula
Percentage change = [(577 - 556) / 556] x 100
Subtract the new number by the original number
577 - 556 = 21
21 ÷ 556 = 0.03776978417266187
0.03776978417266187 x 100 = 3.78%