By Robert Romano

The U.S. economy contracted at an inflation-adjusted 0.7 percent in the first quarter, the Bureau of Economic Analysis reports in its latest update.

The bad news flies in the face of economic projections by the U.S. Federal Reserve, which had been predicting 2.6 to 3 percent growth for 2015 in December. That was downgraded to 2.3 percent to 2.7 percent in March.

That had been considered a weak outlook at the time, with the economy not getting above 3 percent any time soon.

And now, just to get to that modest 2.3 percent for the year, the economy will need to grow at an average annual rate of 3.3 percent each quarter for the next three quarters.

There’s only one problem.

The U.S. economy has not grown at an annual rate of 3 percent since 2005, and not above 4 percent since 2000.

It won’t get out of that losing streak in 2015.

Meaning, it has been a lost decade — amid flattening wages, bottoming interest rates, lower inflation expectations, less borrowing, slowing job creation, aging populations, relatively lower fertility, resulting lower demand, and a financial crisis to boot.

And, whatever tepid growth has been seen since the Great Recession, this may be as good as it gets. At some point, we may have to concede that this is not merely a policy problem. That there may be something more to the slow growth than whether there is a D or an R next to the economy.

As it is, the economy is practically due for another recession, averaging a recession once every 6 to 7 years.

The impact of slower growth is not merely a benign reading, as it has a direct, negative impact on job creation — a critical issue after the recession.

Consider, according to data compiled by the Bureau of Labor Statistics, since the beginning of 2007, the population of those aged 16 to 64 has increased by almost 10 million to 204 million. Yet the amount of people that age with jobs has only increased by 1 million.

As a result, the employment population ratio of working age Americans has dropped from 71.4 percent to 68.7 percent.

If that ratio had remained where it was in 2007, an additional 5.6 million people aged 16 to 64 would have jobs. Note that that excludes retirees. Even after correcting for the Baby Boomers, the situation still looks dismal.

So it is not merely a matter of fewer Americans entering the work force, resulting in slower job and economic growth. We’re seeing that slower growth is undeniably resulting in fewer opportunities per capita than was seen just 8 years ago.

This is the same story being played out in Europe now, plus don’t forget Japan for the past 30 years, where the economy has not grown at all.

What emerges in each case is a demographic time bomb of aging populations and relatively fewer people working. And not just here, but everywhere in the world, where population growth is flattening. Immigration alone will not address the shortfall we are facing.

Overall, we are almost 8 years away from the start of the financial crisis in the summer of 2007. By most accounts, the economy should have recovered by now, but it has not. And what the American people are lacking is a narrative explaining why.

For now, it might be convenient for the political parties to trade partisans barbs about the economy, pretending mightily that things will be different with a mere changing of the guard.

But as the Obama administration has learned in its two terms, at some point, the in-party bears responsibility for the state of affairs.

Should Republicans prove politically victorious in 2016, it will once again be their turn to govern. They can prepare now for what will follow, as the economy has been performing well below expectations for a decade now. Can they take account for the change?

For when the economy fails to recover after the GOP wins, they will own that failure, too, and we may well be having another lost decade. Time for some truth telling.

Robert Romano is the senior editor of Americans for Limited Government.