We can only conclude that you're better off taking the CFA exam in June
When would you rather be locked in your room with a large set of study aids? June, which is now the UK's rainy season? Or December, when most other people have succumbed to full festive abandon?
June is correct. You may also have a higher chance of passing.
According to results for the December 2009 sitting of the CFA Level 1 exam, released today, a mere 34% of December's candidates passed globally. (In an indication that CFA takers are a strangely homogenous breed, the 34% figure held in Asia Pac, EMEA and the Americas.)
December 2008's pass rate was also dire, at 35%. However, the June 2009 pass rate was unfeasibly good by comparison, at 46%.
Does this mean you've got more chance of passing Level 1 in June? Maybe. A spokesperson for the CFA Institute says most people register for the exam in September, giving June candidates an additional six months to prepare.
On the other hand, it may be simply that June 2009 was an anomaly: in June 2008 the pass rate was a depressing 35%. "It could be that people were more worried about their jobs last June and studied harder," speculates another CFA spokesperson.
Nevertheless, we'd recommend a June sitting to be on the safe side. The CFA Level 1 takes around 250 hours to prepare for. Given the final quarter is critical for bonus-related presenteeism at work, December may not be the best time to shut yourself away with a text book.