The growth rate averaged 1.17 percent, with a birthrate of 1.74 percent and a death rate of 0.57 percent, said the report, jointly published by Tibet's regional bureau of statistics and a survey team of the National Bureau of Statistics.

It said the life expectancy of the regional population averaged 67 years, compared with 35.5 years in 1951, the year of Tibet's liberation.

While the report didn't give a breakdown of Tibetans as against other ethnic groups, it said the more than 2.5 million Tibetans made up 92 percent of the regional population in the most recent census in 2003.

Tibet occupies one-eighth of Chinese territory but has the smallest population, with an average of less than three people per square kilometer. The region spans 1.2 million square kilometers, twice the size of France.

The region had only 1.14 million people in 1951. China's family planning policy, which limits most urban couples to one child and rural families to two, does not apply to Tibetans.

The report attributed the population growth to social stability and sustained economic development in Tibet, fostered by assistance from the central government and other Chinese sources.