-15.42% is the change from 506 to 428
Calculation steps:
[( 428 - 506 ) ÷ 506] x 100 = -15.42%
Formula
Percentage change = [(428 - 506) / 506] x 100
Subtract the new number by the original number
428 - 506 = -78
-78 ÷ 506 = -0.1541501976284585
-0.1541501976284585 x 100 = -15.42%