Table 1.1.2 in the GDP release shows the average QoQ contribution by component (in 2009 it was negative 2.4%, though real GDP at the end of Q4 09 vs. Q4 08 actually increased slightly).
The point (I believe) is to reduce noise (i.e. ignore the beginning and ending level) to show what it really felt like throughout the year).
How bad is this 2.4% drop? According to Rex Nutting (via The Big Picture):
Even with the big Q4 GDP, U.S. GDP was down 2.4% in 2009 — the worst showing since 1946 (down 10.9%). Rex also notes “In 2009, business investment fell the most since 1942, while imports fell the most since 1946.”Source: BEA