Muhammad Ali Shah

Let p1 is the price of commodity in year 1 Let q1 is the quantity of commodity in year 1 Let v1 is the value of commodity in year 1 then p1*q1=v1 similarly for 2nd year let p2*q2=v2 now growth in p in percentage = (p2-p1)/p1*100 growth in q in percentage = (q2-q1)/q1*100 growth in value in percentage = (v2-v1)/v1*100 (p2-p1)/p1*100+(q2-q1)/q1*100 is not equal to (v2-v1)/v1*100 i.e. growth in p +growth in q is not equal to growth in v. Now I want to know how much the growth is attributed by price and quantity.Is there any formula or technique? Thanks and Regards