Ratings agencies such as Standard & Poor's have a straightforward job when it comes to rating a company, but the process becomes more complex when the entity being evaluated is a country. Greece, Spain and Portugal have all suffered recent downgrades as a result of the European debt crisis. "What we're looking at is fairly narrow," said Joydeep Mukherji, who rates countries for S&P. "Can you pay your debt fully and on time? What's your ability and willingness to do so?"