-1.04% is the change from 671 to 664
Calculation steps:
[( 664 - 671 ) ÷ 671] x 100 = -1.04%
Formula
Percentage change = [(664 - 671) / 671] x 100
Subtract the new number by the original number
664 - 671 = -7
-7 ÷ 671 = -0.010432190760059613
-0.010432190760059613 x 100 = -1.04%