Recently I made up a spreadsheet to determine correlations between primarily various Vanguard mutual funds.

>The one described here, right?
Yes. I picked Vanguard 'cause they've got lots of funds: domestic, international, growth, value, large cap, bonds, emerging markets ...

>Yeah, so?
So I was interested in allocation between asset classes and determining correlations and ...

>Yeah, so?
Well, I rarely use my own spreadsheets, but I started to use that one myself, but I needed something different so I redid the spreadsheet to look like this:

There's a button called Do which (when clicked) does a bunch of Monte Carlo simulations (picking historical returns at random) and seeing what some "average" portfolio might look like, umpteen years into the future.

>And you plot the distribution of portfolios, eh?
Yes, each time you click that button. I'm glad you noticed that.

Anyway, you pick four stocks, download the prices from Yahoo, then ... well, play with portfolio allocations.
The "Assets" sheet looks like this:

>So how do I get this spreadsheet?

Almost forgot. Just RIGHT-click on the first picture, above, and Save Target Link.