And they're off. Alcoa kicked off the first quarter earnings parade on Monday, reporting an increase in quarterly profit but revenue that fell short. It will be followed by major banks JPMorgan Chase and Wells Fargo this Friday and the rest of the S&P 500 over the next three weeks.
Alcoa is a good proxy on the demand side of the story for the global economy, particularly China, where an economic slowdown has been talked about, but not without debate—China has been growing consistently year after year for decades.
Alcoa CEO Klaus Kleinfeld was just in China and said every company he met with had expectations of 7-8 percent growth. He told CNBC's "Closing Bell" he is optimistic about aerospace, building and construction boosting aluminum sales this quarter.
(Read More: Alcoa Kicks Off Earnings Season With Mixed Report)
Overall, though, most sources are expecting a slow earnings period. S&P Capital IQ said to look for earnings growth for the S&P 500 of just six-tenths of a percent. It expects revenue growth of just 4 percent, which will be down from 4.7 percent a year earlier.