Northern Ireland's 2021 census has gone live, with households in the region now able to complete the 10 yearly survey online.
This year's census is the first with an expectation that the majority of people will submit it digitally.
Census packs are being sent to 840,000 addresses across Northern Ireland from Monday. They are all due to arrive by Saturday.
They each contain an access code to enable people to complete their census online.
Households will have the option of completing the survey in traditional paper format if desired, though they have to proactively request one.
The first tranche of results are expected to be published in June 2022. Those will include top line findings such as Northern Ireland's population calculation.
The region's population is currently estimated to be around 1.9 million.
Data considered significant to Northern Ireland's constitutional future - regarding religious background and national identity - will be published in a second tranche of information in the autumn of 2022.
There are a number of questions new to the 2021 census, including one on sexual orientation and one on renewable energy use.
It is a legal requirement to complete the census, which is used to shape public policy and distribute resources, funding and services.
The official Census Day for 2021 is March 21, though households are able to complete their returns before then.
Census field staff will conduct visits to properties that have not completed their forms.
Those visits will take place under strict social distancing conditions to reflect the current Covid-19 emergency.
While the timeline for the publication of the findings is in line with previous censuses, organisers had originally hoped the results could be published some months earlier than summer 2022.
Social distancing restrictions on staff processing the returns mean that earlier publication target will not now be achievable.
Outlining details of Census 2021, Northern Ireland's Registrar General Siobhan Carey said: "It is important that everyone takes part in the Census, which provides an accurate picture of the people of Northern Ireland.
"The Census form is very easy to complete, taking less than 20 minutes per household and the results will help determine funding and services for the next ten years.
"Over the next few days, each household will receive in the post their invitation to take part. This will have an access code to enable the public to complete their census return online at census.gov.uk/ni
"You don't have to wait until 21st March, once you receive your Census pack through the post, simply go to census.gov.uk/ni to complete the information for your household.
"While we would strongly encourage people to complete their Census online, paper forms are still available for those that need one. Our Census teams will be available to advise anyone who needs additional support."
Ms Carey stressed the importance of the census.
"Just like managing our own households, only if you know the characteristics of the population can you make good decisions about the allocation of funds and services," she said.
"The information gathered in the Census will be used by Government to help plan provision for health, education, transport and so much more."
Dr David Marshall from NISRA, who run the census, spoke to UTV:
For more information visit census.gov.uk/ni or call the Census contact centre on 0800 328 2021.