When nearly 10,000 people surrender firearms certificates you might reasonably assume that nearly 10,000 fewer guns are locked in secure cupboards across the province. But you would be wrong.
In spite of 9,715 fewer people owning guns in Northern Ireland over the last five years, the number of firearms registered in the province has only fallen by 3,000.
The PSNI can't tell us why, or what type of weapons those holding firearms certificates have acquired.
To extract the detail from the current 61,565 issued firearms certificates in Northern Ireland would require an inordinate amount of staff time examining every single certificate - around 5,091 hours' work, the PSNI estimates.
So, unless someone coughs up around £100,000 for a new FOI request, the calibre, velocity and rate of fire of weapons in private hands here will remain a mystery.
The figures provided by the PSNI, when meshed with other data in the public domain, suggest that just over 59,000 people now own 139,399 guns (if you subtract the 2,140 personal protection weapons from the total of 141,539 guns held on certificates).
In 2006, when the number of firearms certificates was recorded as 71,280, the weapons held on those certificates was estimated to be 144,500 - just around 3,000 guns more than are covered today. So it does seem that the 61,565 people who today hold certificates between them acquired around 7,000 new guns during the last five years.
Sinn Fein and others are concerned about the growth of firearms coming into private hands here. It suggests heavy belt-fed machine-guns and other battlefield firearms are in Northern Ireland for display or use in private collections.
The party's spokesman, Alex Maskey alleges a bias in the allocation of firearms permits.
"I know of people in the nationalist community who have had firearms removed and their certificates withdrawn, yet these figures appear to show that those remaining on the register have more guns between them," said Mr Maskey.
"Matt Baggott needs to explain why those who have guns are allowed to add to their armouries while people from the nationalist community are having guns taken from them. I suspect it indicates a political bias in the system."
Whether his suspicions, a figure for battlefield weapons being brought into Northern Ireland as legitimate imports for target shooting at US-style firing ranges is not known because the PSNI can't, or at the minute won't, provide that detail. Many of the additionally acquired weapons - if not the vast majority - will have been bought by existing licence-holders for target shooting and hunting purposes and that's what concerns Green Party MLA Brian Wilson.
"If these PSNI figures are accurate, then they appear to show that more guns are in fewer hands and that is very disturbing," he said.
The MLA said he accepted that, in some cases, the use of firearms was necessary to stop predators attacking livestock. But he said the use of more firearms by a smaller number of people was causing concern.
"I am opposed to the concept of killing animals. I thought we had moved towards a more civilised society, but these figures do cause me concern," added Mr Wilson.
"It appears that we have 10,000 fewer firearms certificates issued in Northern Ireland today, but not 10,000 fewer guns registered.
"The PSNI statistics appear to show that 10,000 guns were taken off the register, but 7,000 new ones were put on which suggests people are adding to their gun collections.
At this point, that question cannot be accurately answered. But it is something Sinn Fein intends to ask the chief constable to explain.