In 1991, it was called the “bungee cord.”

The “it” is the peculiar way that Maine’s economy reacts to recession. About 40 percent of sales tax revenue is tied – or is it bound? – to sales of automobiles and building supplies. In strong economic times, these sectors thrive, the state grows flush and spending increases.

In bad times, though, these sectors plummet and drag state revenues with them. This creates dire situations, like today, as Maine faces an unpleasant budget deficit, in part because these sectors are experiencing the economic equivalent of a nuclear meltdown.

The other primary way Maine raises money, income tax, is no better. Charlie Colgan, this state’s preeminent economist, calls it the “most cyclically vulnerable form of revenue.” Again, when the economy is good, the state prospers. But downturns cause chaos.

So it’s gone, for about 20 years. Since the 1991 recession (when “bungee cord” was coined) there have been repeated calls to untie Maine’s tax revenue from these specific sources – income taxes, cars and building supplies – to stop the boom-bust trend.

It didn’t happen. We have the budget deficit to prove it.

There’s little sense in discussing why. Expanding revenue sources mean new taxes, and new taxes are unpopular. The discussion should be, for lawmakers, what they should now do about taxes to ensure Maine’s peculiarity doesn’t last much longer.

Detail devils abound, we’re sure. But what cannot occur again is Maine lawmakers failing to insulate state government – and therefore the state itself – from this volatile brand of taxation that exaggerates the highs and deepens the lows.

It’s self-defeating, as this current downturn is illustrating with excruciating detail.

Colgan believes if the state acted to broaden its revenues in the interval since the 1991 recession (which took five years for Maine to shake, by the way), budget trouble in Augusta right now would not be as bad.

This seems a clear message to lawmakers, who will debate taxes this session. Past failures to recognize this glaring deficiency have put Maine in a hole it could have avoided, or, at least, in a hole deeper than it needed to be.

Filling the hole is a priority. But so is ensuring we don’t dig another one. Eighteen years ago, this scenario was called our “bungee cord.” Today, we know that analogy isn’t accurate.

It could instead be called our hangman’s knot.