As the first quarter earnings season draws to a close, the results have actually been quite a bit better than expected. The “beat rate,” or the percentage of companies beating the consensus earnings estimate going into the earnings announcement, is running at 67%. The average beat rate of the past five years has been 65%.

Of course, it’s a lot easier to beat when expectations are low enough, and this quarter analysts weren’t expecting a whole lot. Between bad winter weather, a strong dollar and an implosion of profits in the energy sector, analysts went into the season downright cranky.

For an idea of what we should expect going forward, let’s step back from the noise for a moment and look at earnings through a wider lens. Back in April, I recounted an article that Warren Buffett wrote in 1999 but that he just as easily could have written yesterday. At the time, Buffett suggested that in order for stocks to continue rising from their already elevated levels, corporate profits would need to expand to an ever-larger percentage of GDP.

Well…they didn’t, and we had one of the worst bear markets in history from 2000 to 2002.

Today, let’s look at after tax profit margins over time to get a little perspective. As you can see in the chart below, margins have fluctuated in a band of about 4% to 8% since the late 1940s. The white-shaded areas represent periods when the economy was in recession.

Interestingly, profits tend to peak several years before a recession. During the 1990s bubble, corporate profit margins peaked in the mid-1990s and had already been falling for years by the time the stock market bubble burst. Likewise, profit margins had already topped out and had started falling a couple years before the 2008 market meltdown.  And more recently, it looks like profit margins have stalled out and started falling again.

What are the takeaways here?

The first is that the corporate profit margins of the past several years are well outside of the bounds of “normal.” They’ve been made possible by the absolute collapse in capital spending since 2008. Capital spending may fuel the growth of tomorrow, but it’s a major drag on profitability in the short term. Falling bond yields have also lowered borrowing costs, which has boosted earnings further. And labor costs have been kept in check by high unemployment and automation.