-97.45% is the change from 666 to 17
Calculation steps:
[( 17 - 666 ) ÷ 666] x 100 = -97.45%
Formula
Percentage change = [(17 - 666) / 666] x 100
Subtract the new number by the original number
17 - 666 = -649
-649 ÷ 666 = -0.9744744744744744
-0.9744744744744744 x 100 = -97.45%