Surprise! DuPont (NYSE:DD) reported a 25% increase in its first-quarter earnings. While it's good news for DuPont, it's hardly unexpected, seeing as how the company just recently raised its earnings view. However, although there's a pretty marked lack of surprise, it does bode well for an improving economy.

It may feel like just yesterday that DuPont gave us the one-two punch of news in a single week, announcing layoffs followed quickly by a boost of its first-quarter view. (It wasn't yesterday, but it wasn't long ago -- April 14.) So, while today's news is indeed good, it's something that anyone paying attention to DuPont already expected.

Today, the chemicals giant reported first-quarter net income of $668 million, or $0.66 per share, compared to $535 million, or $0.53 per share, in the same quarter last year. If you take out the costs of legal expenses and some other onetime items, the company reported earnings of $0.96 per share, beating Wall Street's expectation of $0.95 per share. Consolidated net sales increased by 15%, to $8.1 billion.

However, upbeat earnings from companies like DuPont and its rival Dow Chemical (NYSE:DOW) tell us a lot about the economic climate. DuPont's range of businesses all delivered strong results, according to the company. And when chemicals manufacturers are boosting earnings and revenues, it means that the global economy is heating up. And if the global economy is heating up, that's good for all of us.

Investors obviously found little to be excited about with DuPont's earnings, as its shares sank just a tad in recent trading.

Regardless, these are signs that the economic rebound is alive and well. When it comes to DuPont itself, many investors are probably waiting for signs that the company's restructuring will leave it stronger than before.

Talk to other Fools about the issues at hand on the DuPont discussion board.

Alyce Lomax does not own shares of any companies mentioned.