st: how to get marginal effect when dependent variable has ln function?

[gjhxmu@sina.com]

Dear statalists,
I have an equation below:
lny=a0+a1*x1+a2*x2+e

and I typed below in the stata:

g lny=ln(y)
reg lny x1 x2

However, how can I get the marginal effect of x1 on y? 

Thank you a lot!

Sincerely,
from Rose

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