-21.99% is the change from 664 to 518
Calculation steps:
[( 518 - 664 ) ÷ 664] x 100 = -21.99%
Formula
Percentage change = [(518 - 664) / 664] x 100
Subtract the new number by the original number
518 - 664 = -146
-146 ÷ 664 = -0.21987951807228914
-0.21987951807228914 x 100 = -21.99%