By Dirk van Dijk of Zacks.comNEW YORK ( TheStreet) -- In the third quarter, the economy grew at an annual rate of 2.0%, up from 1.7% in the second quarter, but down from the 3.7% pace in the first three months of the year. The growth rate was in line with consensus expectations, and frankly a bit better than I was expecting. So how did we get to the 2.0% overall growth? What parts of the economy were growing and thus adding to growth, and which parts were acting as a drag on growth? Since the different parts of the economy are of very different sizes, and some tend to be relatively stable, while others can be very volatile, I will focus on the contributions to growth. In other words: growth points, not the percentage growth rates. After all, a small percentage change in a very big part of the economy can have more impact than a big percentage change in a small part of the economy. I will follow the familiar Y = C + I + G + (X - M) framework, where Y = GDP, C= Consumption, I = Investment, G= Government, X = exports and M = imports.