Each day at 2pm, the government releases data showing how many people have died in UK hospitals after testing positive for coronavirus – and how big an increase that represents over 24 hours.

Simple, right?

Sadly, it isn’t. The total figure is likely to be too low, and the daily increase it represents could be significantly too low or too high. Let us explain.

Late recording of deaths

The daily increase includes not only deaths that occurred over the 24 hours up to 5pm on any given day, but also deaths from earlier days that have only now filtered through to the data collection taking place centrally.

For instance, a person who died on March 20 might take more than a day to verify – say, if there is confusion over test results or a delay in sharing the information from a particular trust. Their death might then finally be included in the total several days later – say, March 30 – meaning it would appear to be part of the daily increase on that day even though it wasn’t, actually, even from that week.

By the same token, the true number of deaths over the last day is likely to have been higher than the most recent figure shows as some of today’s deaths will not yet have reached the government’s statisticians and will instead appear in future counts.

Only deaths in hospital are included

Unfortunately, that isn’t all. It only includes deaths in hospitals, not accounting for suspected or even confirmed cases who have died in the community – at home, in care homes or prisons, or elsewhere.

The Office for National statistics now releases weekly data on all those deaths as well but they aren’t included in the DHSC’s daily data dumps.

Here’s more about why the official number of daily confirmed infections – as opposed to deaths – is also likely to be nothing like the true figure.

The four nations don’t add up

There’s one last problem.

The DHSC is meant to release figures at 2pm. If it does, the story ends there. But it almost never makes that deadline, which often means the four devolved authorities – England, Scotland, Wales and Northern Ireland – end up releasing their own individual death counts first.

No problem, right? Add them all up and you’ve got the UK figure. Again, sadly, it’s not that simple.

HuffPost UK spent some time in discussion with the department to understand why the DHSC figure never matched the four totals. Full detail is here.

In summary, though, the four nations continue working on their own numbers even after releasing them to the government, so what they release separately could be more up-to-date than the DHSC’s own release.

That doesn’t, of course, explain how the DHSC ends up releasing data after each of the nations has reported.