Like many countries, Pakistan allocates federal resources to its provinces and administrative regions based on population.
Trouble is, Pakistan's last census took place nearly two decades ago, and insecurity and political wrangling have stalled efforts to carry out a fresh head count.
This month Pakistan launched a national census for the first time in 19 years, deploying 200,000 soldiers alongside 118,000 civilian enumerators in an effort to count and compile demographic data on every person.
The census will not only count the population and ethnic and faith groups in each of the country's four provinces and other administrative units. It will also determine provincial shares of federal revenue and subsidies, as well as shares of seats in the National Assembly and civil service quotas.
Transgender people will also be counted for the first time, officials said.
"We will be able to share provisional summary results of the data by the end of July," said Asif Bajwa, Pakistan's chief census commissioner.
In a country with desperate shortages of electricity and other basic infrastructure, experts say a fresh count is badly needed. The constitution requires a census every 10 years. Pakistan's population is estimated to have grown by as much as 40% since the last census, in 1998, counted 130 million people.
"Since then the country is being run on guesstimates," said Abid Suleri, head of the Sustainable Development Policy Institute, a think tank in Islamabad, the capital.
"The best plans and policies fail to deliver, partially, when we do not have our numbers right. It is like stitching someone's clothes without knowing the age, height, weight and measurements."
But even before door-to-door counting began last week, the census stirred controversy as women's rights groups, smaller provinces and ethnic and religious minorities voiced concerns over the process.
Despite acknowledging that the 1998 census undercounted women and girls, officials this year did not appoint any female census workers, according to Sarwar Bari, a human rights activist in Islamabad. In many areas, male census workers would not be able to interview women because of religious and cultural taboos, Bari said.
"There is not even a single female enumerator appointed in Punjab, the largest province of the country," Bari said. "Male enumerators will face problems in counting women."
Ethnic Baluch and Pashtun political parties, which have long agitated for greater autonomy from the federal government, fear that officials in Punjab will attempt to manipulate census figures to maintain the province's large share of national resources and political clout.
"The census has become a political — in fact a politicized — issue in Pakistan," Suleri said.
Currently, Punjab holds 183 seats in the 342-member assembly, meaning it can unilaterally elect the prime minister. The current prime minister, Nawaz Sharif, hails from Punjab.
"The federal government had planned to manipulate census figures to maintain the hegemony of Punjab over smaller provinces," said Mian Iftikhar Hussain, the general secretary of the Awami National Party, a Pashtun nationalist party.
The party also complained that census data from its heartland in Khyber Pakhtunkhwa province and the adjacent tribal region would be counted in Islamabad because of a lack of equipment locally.
"We believe that [bad faith] intentions are involved," Hussain said, adding that ethnic Pashtuns might not accept the census results.
In the federally administered tribal areas, lawmakers have raised concerns that their population will be undercounted because residents have fled their homes to escape Pakistani counter-terrorism operations and U.S. drone strikes against suspected militants.
Residents of the Orakzai tribal region boycotted the campaign for two days, saying that census takers were going to areas that residents had vacated years ago.
In the southwestern province of Baluchistan, Pakistan's poorest, some lawmakers filed a lawsuit to stop the census, saying they feared that thousands of mainly ethnic Pashtun refugees from Afghanistan — many of whom have lived there for more than three decades — would mistakenly be included in the count.
Afghans in Pakistan are often accused of carrying fake citizenship documents to avoid deportation. The presence of the refugees — and the fact that many ethnic Baluch have migrated to other provinces — could make the Baluch a minority in the province that is their heartland, according to the lawsuit by the Baluchistan National Party.
The government has no mechanism to collect accurate census figures in the absence of the local population, who were forced to migrate to other parts of the country," said Baluchistan National Party leader Ghulam Nabi Marri. In response to the lawsuit, a provincial court directed authorities to exclude Afghan refugees from the census.
In several provinces, leaders of the Sikh community have objected to their faith being left off the census forms. Sikhs, whose religion was founded five centuries ago in what is now Pakistan, have to list themselves as members of "other" religions.
There has never been an accurate count of the Sikh population of Pakistan, which is estimated to be in the tens of thousands. There are about 20 million Sikhs in neighboring India.
It would mean "total disrespect to the community if their religion is not mentioned and they remain unrecognized in a land which means the most to them," Sardar Ramesh Singh, leader of the Pakistan Sikh Council, told the daily Dawn newspaper.
The census is expected to cost Pakistan about $178 million.
Special correspondents Sahi and Ali reported from Islamabad and Peshawar, Pakistan, respectively, and Times staff writer Bengali from Mumbai, India.
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