Extending a trendline beyond the data markers

Hi, 

I'm in need of help.. In the graph below, I want to extend the shown lognormal trendline over the remaining part of the x-axis. The circles are actual data but they stop midway on the x-axis. I couldn't figure out how to do this. Kindly advise. I don't care about the confidence intervals in this case, just need the mean trendline extended. 

Sincerely, 

Peeyush