# econometric data

I have a quit straight forward question: I have a variable which is coal rents measured in 2009 US Dollar. I would like to set this variable in relation (ratio) to another variable which is PPP Converted GDP Per Capita (Chain Series), at 2005 constant prices.

$\frac{\rm coal \;rent}{\rm GDP(ppp)}$

I would like to run some regressions with this variable as my independent variable. However I´m not sure whether I have to account for inflation from 2005-2009 when doing the ratio of $\frac{\rm coal \;rent}{\rm GDP(ppp)}$.....I dont have much economics backround :) maybe some of you are able to give me a theoretical as well as a practical hint....

thx and happy new start :)

• You can use TeX typesetting by enclosing the code in dollar signs, i.e. \$\frac{a}{b}\$ displays as $\frac{a}{b}$. – Alex Becker Jan 1 '14 at 23:39