Okay, let's sum up... You have an official website that contains data. I assume this data is stored somewhere on this webserver. Probably in some database. Then why not retrieve the data directly from the source?

If you're using SQL Server for this data then you could add a stored procedure or view to the database that will provide the data in whatever way you like. (You need to have SQL knowledge, though.) I think it's even possible to have Excel connect to this database directly and thus always keep it's contents uptodate, but that really depends on the structure of your data and your system.