6420% is the change from 15 to 978
Calculation steps:
[( 978 - 15 ) ÷ 15] x 100 = 6420%
Formula
Percentage change = [(978 - 15) / 15] x 100
Subtract the new number by the original number
978 - 15 = 963
963 ÷ 15 = 64.2
64.2 x 100 = 6420%
Example