How to plot risk-cost frontier using 2 related data series

Please guru here advise how to plot the graph with the curve shown in link below, and there are 2 series of data e.g. risk, return that each line of date are related each other, for example, risk 99.99 relates to return 15.11 while 99.98 relates to return 16.20.

http://tradingchief.com/glossary/7186.gif

Thanks you very much for all your advice, I've tried so many commands to have it done but still not work yet.

[Thossapron]

Please anyone could advise, I tried to modify the sourcecode used for efficient frontier but it did not work at all.