Dont forget CIA World Factbook for Geography paper II statistics.

@New Horizon: There are certainly scoring and non-scoring subjects, although trends are hard to predict. For instance, Forestry and US History nearly every year produce a few 80s and a number of 70s, while IR will NEVER give anyone an 80. Choosing according to your aptitude is important but NOT at the risk of creating a combination that will limit you to a 600-650 total range. Scoring trends are pretty important and must be discovered through careful study.