MACAO, Dec. 20 -- Chinese President Xi Jinping attended the inauguration of the fourth-term government of the Macao Special Administrative Region (SAR) here on Saturday morning.

The following are some basic facts about the Macao SAR:

China officially resumed the exercise of sovereignty over Macao on Dec. 20, 1999, when the Macao SAR was established and the SAR's constitutional document, the Basic Law, came into force on the same day.

The Basic Law lays down a political and administrative framework of the Macao SAR. Under the principles of "one country, two systems" and "Macao people governing Macao," the SAR exercises a high degree of autonomy in line with the Basic Law.

Due to land reclamation along its coastline, Macao has grown in land area from 23.8 square km in 1999 to 31.3 square km. Macao has a population of over 630,000, with a population density of 18,900 per square km, and the northern part of the SAR is one of the most densely populated areas in the world.

Though a small economy, Macao pursues an open economic policy. It has one of the lowest tax regimes in the Asia Pacific region. In addition, as a free port and a separate tariff zone, which has no foreign exchange controls, Macao is also an active player in the regional economy.

Firstly legalized in the mid-19th century, Macao's casino gaming has developed a very close relationship with the tourism industry and become a pillar of local economy.

In 2002, the government of the Macao SAR liberalized the gaming industry, bringing new momentum to Macao's gaming sector and the entire economy. With the influx of foreign direct investment in the sector, the gross revenues of Macao's gaming industry increased to 361.87 billion patacas (45.33 billion U.S. dollars) in 2013 from 14 billion patacas in 1999.

Macao's gross domestic product (GDP) reached 413.47 billion patacas (51.76 billion U.S. dollars) last year from 50.27 billion patacas in 1999, with an average annual growth of 16.2 percent. The GDP per capita jumped from 15,000 U.S. dollars in 1999 to 87,000 dollars in 2013, which ranks the second highest in Asia and the fourth in the world.

Meanwhile, the unemployment rate has dropped from 6.3 percent upon Macao's return to China in 1999 to 1.7 percent. The average monthly income has tripled to 15,000 patacas from 4,920 patacas and the life expectancy of local citizens has risen from 80.7 years in 1999 to 85, the second longest in the world.

Aside from casinos, the SAR is also a popular travel destination. The SAR recorded some 29.3 million visitor arrivals in 2013.

Macao boasts the unique assimilation and co-existence of Chinese and Western cultures. The Historic Center of Macao, a collection of over 20 locations, was inscribed on the UNESCO World Heritage List in 2005, making it the 31st designated World Heritage site in China.