Iraq is conducting a nationwide census, its first attempt to gather demographic data since 1987 when Saddam Hussein was still in power.

The Ministry of Interior announced a two-day curfew for the extensive operation, which will see 120,000 researchers gathering data from households in all 18 of the country’s governorates on Wednesday and Thursday.

Ministry of Planning spokesman Abdul-Zahra al-Hindawi said that the census, carried out with the United Nations Population Fund (UNFPA), would reveal “the reality of Iraq in its smallest details”, enabling authorities to pinpoint gaps in health, education and housing provision.

Iraq has spent much of the past few decades devastated by conflict and sanctions, the 2003 United States-led invasion that toppled Hussein followed by sectarian struggles and the emergence of the ISIL (ISIS) group.

The act of counting the population could prove contentious, with the census expected to have profound implications for Iraq’s resource distribution, budget allocations and development planning.

In particular, it has reignited tensions between Baghdad and Iraqi Kurdistan, the latter fearing any documented decline in the Kurdish population will reduce the group’s political influence and economic entitlements in the country’s sectarian power-sharing system.

A team from the Planning Ministry carries out the national census in Kirkuk [Ako Rasheed/Reuters]

The count in territories such as Kirkuk, Diyala and Mosul – where control is disputed between the central government in Baghdad and the semi-autonomous Kurdish regional government in the north – has drawn intense scrutiny.

Ali Arian Saleh, the executive director of the census at the Planning Ministry, said researchers from all ethnic groups – Kurds, Arabs, Turkmen, and Christians – would conduct the census in disputed areas to “ensure fairness”.

Saleh said the Kurdish region’s share of the national budget – currently 12 percent – is based on an estimated population of six million. He estimated Iraq’s total population to be 44.5 million.

The census, which will gather information from households on issues like health, education and employment, includes religion but does not differentiate between sects, such as Sunni and Shia Muslims. Unlike previous counts, it excludes ethnicity.

Demographics are likely to have shifted with the exile of hundreds of thousands of Christians, and also of tens of thousands of Yazidi families who were displaced from Sinjar by atrocities committed by ISIL.

The last nationwide census in Iraq was held in 1987. Another one held in 1997 excluded the three northern provinces that make up the semi-autonomous Kurdistan region.