But I don't want to be burdened with entering these manually every day OR paying a wad for data feeds. Do you know of an inexpensive but easy solution?
Depends on your definition of "inexpensive."
Here are some possibilities:
[1] I think that there is a way to download individual data points, e.g., the closing price of a single index, into a single cell of Excel, but I don't know how it's done.
[2] I'm also pretty sure that there are Excel add-ons you can buy which would do this, but I don't know their names, nor whether they are easy to use.
[3] Larry Dudash uses a data-feed/system which is relatively inexpensive, i.e., less than $100 per month, and which allows him to update a spreadsheet with a single click. I don't remember what system/provider it is, but he could tell you.
Second problem, I'm not a math wizard or software programmer and I'm a novice in Excel.
Welcome to the Ignorant Non-Geek Club -- which is composed of those of us who were too dumb to major in something useful in college yet are just smart enough to have figured out -- now that it's too late -- that we messed up by not doing so. {g/ng}
I assume my system could be developed just using Excel (?)
Yep. No problem. A little time consuming to set up, but actually quite easy to do.
Do I need to take a class in Excel...?
Heck no, I figured it out and I was a poli-sci major for garsh sakes! {g/ng}
Take a look, in the iBox on #board-1752, at "[3] Rate of Change (unsmoothed)"