  This work studies the Zipf Law for cities in Brazil. Data from censuses of
1970, 1980, 1991 and 2000 were used to select a sample containing only cities
with 30,000 inhabitants or more. The results show that the population
distribution in Brazilian cities does follow a power law similar to the ones
found in other countries. Estimates of the power law exponent were found to be
2.22 +/- 0.34 for the 1970 and 1980 censuses, and 2.26 +/- 0.11 for censuses of
1991 and 2000. More accurate results were obtained with the maximum likelihood
estimator, showing an exponent equal to 2.41 for 1970 and 2.36 for the other
three years.
