Theresa May fired off a volley of stats about the NHS under the Conservatives at this week’s Prime Minister’s Questions.

But some claims only tell half the story about what’s going on in the health service.

Let’s take a look.

Claim 1: The Conservatives “are able to give the NHS the biggest cash boost in its history”

In 2018, the government announced that an extra £33.9 billion will be made available to the NHS in 2023-24. Not accounting for inflation, this is indeed the biggest single cash budget increase for the NHS announced by any government.

But that’s not quite as amazing as it sounds.

Governments almost always increase spending on the NHS year-on-year, and because the value of money almost always falls due to inflation, next year’s total will almost certainly be bigger than the year before in cash terms. So it’s pretty easy to have broken the previous record every year.

That’s why NHS economists insist on talking about funding in real terms, and they often judge governments by the pace at which they are increasing health spending – the annual growth rate.

Mrs May didn’t mention that since taking office in 2010, the Conservatives have been more parsimonious with the NHS than the last government.

As FactCheck found last year, health budgets grew at an average rate of 1.3 per cent a year between 2010 and 2016, compared to an average of 5.6 per cent a year between 1997 and 2010 under Labour.

Looking further back, the Institute for Fiscal Studies (IFS) says that health spending growth under the first six years of Conservative rule was “substantially below” the historic average between 1955 and 2016, when budgets grew by 4.1 per cent a year.

That extra cash promised by Mrs May will take the annual increase to 3.4 per cent between 2018-19 and 2022-23. This is more generous than previously planned but not particularly impressive in historical terms.

The independent King’s Fund think tank says the money pledged is in line with the “minimum increase needed to maintain quality and access to care given the growing and ageing population and rising burden of chronic disease”.

We looked at these figures in more detail in 2018.

Claim 2: “And who were the only party in government that cut funding for the NHS? The Labour party”

It’s true that in the final years of the last Labour government, healthcare spending dropped by 0.2 per cent in 2009 and 2.1 per cent in 2010.

However, over Labour’s 13 years in power from 1997 to 2010, healthcare budgets grew by 5.6 per cent a year on average.

They grew by 1.3 per cent a year under the Conservatives between 2010 and 2016.

Claim 3: “Is this government giving the NHS £7 billion? No. Is it giving it twice that? £14 billion? No. It is giving the NHS £20 billion.”

Mrs May was referring here to a pledge Labour made back in 2017 to increase spending on NHS England by around £7 billion a year between 2017-18 and 2021-22.

She compared that figure with the amount the Conservatives have promised to spend in 2023-24. As we have seen, in cash terms that sum is an extra £33.9 billion. In real terms – adjusting for inflation, it is indeed just over £20 billion.

Clearly, £20 billion is more than £7 billion, but this is an apples-and-oranges comparison.

Labour’s 2017 manifesto never said what they would spend in 2023-24 – the figures they put out referred to earlier years.

And Labour’s policy was to add £7 billion a year on top of what the government had already committed in plans made in 2015. It’s not clear that the £7 billion and £20 billion figures are starting from the same baseline.

It’s fair to say that Labour have changed their tune on NHS funding. In 2017, they pledged to increase budgets by 2 per cent a year on average, but lambasted the Conservatives in 2018 when the government announced what Labour called an “insufficient” boost of 3.4 per cent.

But Labour have now upped their offer. In 2018, the day after the government’s announcement, Labour promised to increase NHS spending by 5 per cent a year. So the Labour spending promise Mrs May referred to is now out of date.