Issues with data in the Rolling Electronic Census mean the number of people leaving the island may have been over estimated.
The last figures for Guernsey's overall population showed 64,781 as at 31 December 2023.
Population has been steadily increasing as more people move to Guernsey to take up work, something encouraged by the States to counter the ageing demographic.
But new computer systems in Revenue Services and more data analysis show that the Rolling Electronic Census could be wrong.
In December '23 it showed 2,226 people had left Guernsey but more came to live, meaning net migration was 910:
'These issues are likely to have caused historical outward migration statistics (i.e. the number of people moving away from Guernsey) to be under-stated.
'While it is normal for these statistics to be re-stated by small amounts each time they are issued after new information comes to light, it is now expected that the next publication could include a downward revision of the total population of up to 3% - a larger revision than is normal.'
That could be around 1,800 people, roughly 3% of the current figure.
The States say that making sure the next set of figures are accurate is a priority and it has resourced IT system changes and data validation, which now need to take place.
The population figure hasn't been published for 18 months but figures for employment and earnings are more up to date.
There will be a delay in publishing the next set of figures, which were due out today:
'Accuracy of the statistics remains the priority. It is important that the public can have confidence in the published statistics.'
Guernsey joins calls for peace in Gaza
Cimandis to pull food wholesale operation from the Channel Islands
New External Relations Lead selected amid Guernsey Police investigation
Guernsey deputies express dismay over famine in Gaza
Guernsey education experts help shape new National Writing Framework
Guernsey's oldest pub closes temporarily
Foundation laying begins at Guernsey's Wildlife Hospital
New Chairman For Guernsey's Island FM
