151210 \Angolan President Jose Eduardo dos Santos (L) looks on during his first visit to South Africa for bilateral discussions with South African President Jacob Zuma in Pretoria, December 14, 2010.The talks will likely result in energy and business deals between the two states as well as South Africa possibly extending a credit line to Angola in exchange for oil. REUTERS/Siphiwe Sibeko (SOUTH AFRICA - Tags: POLITICS)

Luanda - The oil rich southern African nation of Angola began its first census in almost a half century on Friday, a survey that could have far-reaching repercussions for government policy.

Around 100 000 census takers will be involved in the $200 million project, which will conclude at the end of the month, according to organisers.

It is the first census in the country since 1970, when Angola was still a Portuguese colony and the population was estimated at 5.6 million.

Today it is closer to 21 million and the country has come through a brutal civil war transformed. Today it is sub-Saharan Africa's third largest economy and second largest oil producer.

Besides population size, the survey will give a more precise picture of distribution by sex and age, as well as pinpointing some potentially embarrassing realities for the ruling class.

Although Angola's government is rich, its people are among the poorest on earth and unemployment is rife.

“The collection of complete information and statistics about population is a very important step in development and in providing services facilities”, said US Secretary of State John Kerry during his visit in Luanda earlier this month.

Angola has been ruled by President Jose Eduardo dos Santos for nearly 35 years. He was re-elected for another five year term in August 2012.

Results of the census are expected to be known in around four months.