How do I expose Excel 2003 Spreadsheets to PerformancePoint 2007?

I am working on a PerformancePoint 2007 project. I have a bunch of Excel spreadsheets, and I need to get at the data. The users need to continue to enter data, they have Excel 2003, and I won't be here forever. If the users had Excel 2007 I could just use Excel Web Services in MOSS 2007, but that's a no go.

What are your recommendations for getting the data into a usable state?

Some options are:

• create an SSIS package to import the data into SQL Server, and teach them how to run the package as time goes on
• get the data into SQL Server (SSIS) and then build a web front-end that lets them enter new data
• use Access as a proxy for getting the data into SQL Server and use its web access pages to let the users enter new data

Any other ideas? I've heard "Business Data Catalog" thrown about, but I'm not sure how it would help...

Thanks.

Here's what I did:

1. Create SharePoint lists that duplicate the spreadsheet functionality
2. Copy and paste the current spreadsheet data into the list
3. Tell them to throw away the spreadsheet and make their updates to the list (export to Excel if they need a special chart or something
4. Use Simego Data Synchronisation Studio to import the data into SQL Server on a regular basis
5. Point PerformancePoint to the database for analysis.