-2.21% is the change from 679 to 664
Calculation steps:
[( 664 - 679 ) ÷ 679] x 100 = -2.21%
Formula
Percentage change = [(664 - 679) / 679] x 100
Subtract the new number by the original number
664 - 679 = -15
-15 ÷ 679 = -0.022091310751104567
-0.022091310751104567 x 100 = -2.21%