The Economist:

DO ACADEMIC economists focus too much on America? Yes: a sample of 76,000 papers published between 1985 and 2005 shows that econo-nerds are infatuated with the “land of the free”.
There were more papers focused on the United States than on Europe, Asia, Latin America, the Middle East and Africa combined (see chart). And for the world’s top-five economics journals–where publication of a paper can push a young researcher towards a full professorship–the imbalance is yet more marked. Even accounting for the fact that lots of economic research (and often the best) comes from American universities, the bias persists.
The world’s poorest countries are effectively ignored by the profession. From 1985 to 2005 Burundi was the subject of just four papers. The American Economic Review, the holy grail for many academics, published one paper on India, by some measures the world’s third-largest economy, every two years.