Corporate tax solutions provider Vertex has been tracking the U.S. average sales tax rate since 1982. Last year, the average hit a new record — 5.468 percent — according to the firm’s latest report, published this week.

Seven states increased their standard rate in 2009 (also a record).

More worrying, perhaps, for the companies that have to collect and remit these funds, is the fact that tax authorities are levying more and more new sales and use taxes, and they’re changing the ones they’ve already established more frequently.

The numbers are jaw-dropping. Since 2000, Vertex has recorded:

• 2,631 new sales and use taxes — an average of 263 per year.

• 5,242 changes in sales/use tax rates — an average of 524 per year.

Monitoring changes of this magnitude is, of course, a colossal challenge for companies that do business nationwide and makes total nonsense of calls to open the Internet up to transaction taxes, as I noted a couple of weeks ago.

No relief from new sales/use taxes and higher rates is in sight, however, as long as states’ revenues continue to drop — as they did for the fifth straight quarter at the end of last year (though the trend does seem to be slowing). See the Rockefeller Institute’s latest report on state revenue collections, available here. ###