Posted by By Alex Last BBC News, Lagos on
In the poor tenements and slums of Nigerian's main city of Lagos, census workers came to count the population.
In the poor tenements and slums of Nigerian's main city of Lagos, census workers came to count the population.
Clipboards in hand, they asked everything from people's age to what kind of toilet they used. Once counted, thumb prints were put on the form and fingernails marked with indelible ink.
Many residents were pleased that they had not been ignored in the country's first census for 15 years.
"I am very happy and surprised that they came here. It's the first time I have ever been counted," said Awhanji Madelenu from Makoko slum, where her house stands on stilts among the rotting waters on the edge of the city's lagoon.
But there have been complaints around the country - from herders in the north-eastern state of Yobe, to a densely populated district of the Lagos - that they had not been counted in the seven-day operation.
| There is nowhere in the world where you achieve 100% enumeration |
The Nigerian National Population Commission (NPC), which ran the census, says overall it has been a success.
NPC chairman Sumaila Makama said it was inevitable that a few people would be missed out, but almost all Nigerians had been counted.
"There is nowhere in the world where you achieve 100% enumeration, but it is our aim to count all Nigerians, everybody who has made himself available to be counted," he said.
Backlog
The logistical challenge facing the census operation was huge. Nigeria's population is estimated to be between 120 million and 150 million.
The government says the census is to help plan development and had been planning it for three years.
But from the very start the operation was dogged by problems.
There were delays because of a lack of census forms and arguments with the enumerators over payment.
The resulting backlog forced the government to extend the count from five days to a week.
There was some violence in the east of Nigeria directed against census workers, blamed on the Biafran separatist group Movement for the Actualisation of the Sovereign State of Biafra (Massob); though not on the scale many had feared.
Real test
Two of the most sensitive issues of religion and ethnicity were deliberately excluded from the questionnaire.
The government was concerned that the results could trigger sectarian and ethnic riots. Just last month, more than 100 died in inter-communal violence in three towns.
But the census form did include questions about people's origin. In Nigeria, that can give at least a clue as to people's likely ethnicity or religion.
One of the biggest challenges for this census is credibility.
In the past, censuses have been marred by widespread allegations of fraud and manipulation.
In Nigeria, the higher a state's population the more money it gets from the federal government. Allocation of some government posts is also supposed to reflect different regions' populations.
The NPC says this time it will be fair.
It has digital processing of the forms, and satellite positioning was used to identify the areas to be counted. The information is to be collated over the next few months.
But in the end, it will only be when the results are finally announced, that the real test comes.
Will Nigerians accept that the country's countless millions have finally been counted?