Suppose I have the relation:
$$XY = Z$$
I want to find the 'contribution' or share that $X$ and $Y$ makes to $Z$. So I ln both sides:
$$\ln(X) + \ln(Y) = \ln(Z)$$
We could divide by $\ln(Z)$, so I have
$$\frac{\ln(X)}{\ln(Z)} + \frac{\ln(Y)}{\ln(Z)} = 1$$
Is it correct to say $\frac{\ln(X)}{\ln(Z)}$ is somehow the contribution of of $X$ to $Z$?
