Last year, I wrote in Forbes about whether Missouri is a "low tax state." (It isn't.) I explored how Missouri compared to other states on a variety of taxes. At the time, by the Tax Foundation's metrics, Missouri's combined state and local sales taxes ranked 14th highest in the country.

This finding probably surprised a few Missourians, but it shouldn't. Missouri's state sales tax may be relatively low at 4.225 percent, but locally imposed sales taxes nearly double the average sales tax paid in Missouri stores. This includes extra sales taxes in special taxing districts like Kansas City's Power & Light District, which can pump the sales taxes actually paid by consumers to well over 10 percent. These sales taxes are, of course, in addition to the state's income and property taxes, which aren't exactly low either. This is why Missouri isn't a "low tax state."

The Tax Foundation released its 2015 sales tax rankings, and . . . well . . . Missouri still ranks 14th at a rate of 7.81 percent, well ahead of 29th-ranked Florida (6.65 percent), which, of course, doesn't have an income tax. The Tax Foundation's report makes special mention of the failure of Missouri's transportation sales tax last year, which would have added another three-quarters of a percent to the state's already-high sales tax. Had Amendment 7 passed and bumped the state's average sales tax to over 8.5 percent, chances are very good that Missouri would have jumped into the top 10 of high sales tax states, ahead of states like California (8.44 percent) and New York (8.48 percent). Missouri's sales taxes are already bad; this year it is cold comfort to know that they could have been worse.

Missouri needs substantive, across-the-board tax relief. There's still time for the legislature to act this year—at least on the income tax—but the clock is ticking.