Any income accrued on investments should be paid out to heirs, though, to avoid paying up to 39.6% income tax on interest and dividends.

FORBES: An Estate Plan Worthy Of Scrooge

Better infrastructure and education in the more urbanised north mean that the benefits of Mexico's membership of the North American Free-Trade Agreement have accrued there, while income in the south stagnates because of low productivity.

ECONOMIST: A tale of two Mexicos