500% is the change from 66 to 396
Calculation steps:
[( 396 - 66 ) ÷ 66] x 100 = 500%
Formula
Percentage change = [(396 - 66) / 66] x 100
Subtract the new number by the original number
396 - 66 = 330
330 ÷ 66 = 5
5 x 100 = 500%
Example