Financial Lifepath

I would like to create a system that captured a clients financial position, their long term goals and expenses. The system would then graph their capital net worth over their lifetime. I would then be able to save this scenario and compare it against changes in the future. Each year (or more frequently) I would be able to enter their progress so that we can see how it compared to the original plan. I would like this system to work over the internet (as part of my website). I would also like the system to print out a report on all the inputs as well as the graph. The formulas I can assist in designing, but I lack the knowledge to create a full workable system. At the moment I use excel and save individual files, I would like to have it all as one system though.