Here are 3 theories about why stocks are puking, and what they mean for the economy

Stocks are down sharply in the past two days. I look at three possible reasons why. One story is happy: Maybe faster business expansion and more competition for workers will hurt corporate profits but lead to better deals for workers and customers. Maybe investors are worried that central banks will raise interest rates. Most worryingly: Maybe higher budget deficits mean we'll need higher interest rates, regardless of what central bankers are thinking. So, why are stocks down 1,700...