GDP is one of the most widely used measures to gauge the health of the economy. Fourth-quarter GDP was revised slightly upward today from 1% to 1.4 %. While the revision topped expectations, it is still a fairly weak reading.

However, the numbers often get revised, sometimes by a percent or more, so watching them month to month isn't going to get you a clear read on economic strength.

On top of that, the numbers are seasonally adjusted, and even the government admitted that it isn't sure it is adjusting for weather and other factors appropriately.

But there's another number that we can use to gauge our economic health: Gross Domestic Income.

While GDP measures economic activity on expenditure—including goods, services, and technology—GDI measures the income earned while producing those goods and services.

GDP and GDI should theoretically match up, but because they are calculated in different ways, there is some margin of error.

It's almost like taking a snapshot of the economy from a different angle. And GDI is becoming an increasingly popular measure.

Today GDI came in at 0.9 percent, which confirms the weak GDP reading.

At least anyone looking for a bright spot in the economy can point to the fact that expectations were lower than what we got.