Quote:

I have the total sales of a product for 5 years.

I have the % growth by year for each of the 5 products that combine the total

and i need to find the %split of the total, by product.

i tried solving by simultaneous equations but these seem to give negative numbers.

Possibly because the source data is inaccurate.

I wondered if this was the best way or if there were any way to estimate the splits?

$\displaystyle \begin{array}{c|ccccc|} \text{Product} & 2006 & 2007 & 2008 & 2009 & 2010 \\ \hline a & 23.3\% & 19.1\% & 6.2\% & 10.5\% & 20.8\% \\ b & 14.0\% & 14.7\% & 24.5\% & 0.5\% & 8.6\% \\ c & 12.0\% & 8.7\% & 10.4\% & 10.0\% & \text{-}2.3\% \\ d & 26.3\% & 18.0\% & 2.9\% & 2.9\% & 15.0\% \\ e & 4.4\% & 13.7\% & 13.2\% & 0.2\% & 4.8\% \\ \hline \text{Total} & 9369 & 10827 & 12383 & 12524 & 13876 \\ \hline \end{array}$

The table above shows the percentage increase of each product (a-e)

from the previous year, and the total sales of a-e for that year.

I need to know the split of a-e in making up the total for each year. Ideas?