-98.06% is the change from 670 to 13
Calculation steps:
[( 13 - 670 ) ÷ 670] x 100 = -98.06%
Formula
Percentage change = [(13 - 670) / 670] x 100
Subtract the new number by the original number
13 - 670 = -657
-657 ÷ 670 = -0.9805970149253731
-0.9805970149253731 x 100 = -98.06%