The surprising things we learn when we count everyone - a tour of the UK census through time.

We also figure out just how many parking officers there are versus soldiers in the British army.

Who really does all the housework? Plus - 20 years of ‘Freakonomics’ with Stephen Dubner.

And finally - were there really three wise men who visited baby Jesus? And were they kings as the Christmas hymn would lead us to believe?

Presenter: Tim Harford

A loyal listener wrote in to question this claim made by neuroscientist Dr Daniel Levitin: "Here in the US valium in a pharmacy might be $3 that same pill in a hospital setting might be $750."

Our listener was shocked at how one pill can cost 250 x more in a hospital setting than in a pharmacy. But can it? Sort of.

We turned to Elisabeth Rosenthal to take us on a dive into the frankly shocking world of US Health costs.

Presenter: Tim Harford

The NHS is warning of an unprecedented flu season - we check what the numbers say.

Is there really a mass exodus of Brits leaving the UK due to Labour tax policies? We look at the latest emigration figures.

We take a look at the prison service’s curious habit of letting prisoners out early – or keeping them in for too long - is there a trend?

Plus - why the US economy can’t grow at 25 percent a year.

Presenter: Tim Harford

Whether we like it or not, global warming is happening. The global temperature has already gone up, and it’s going to go up more, because the atmosphere is already full of carbon dioxide and other greenhouse gases, and we’re continuing to add to that stock. Quite how much it will increase by is a very important question for all of us.

Around the world, many countries are concerned about tackling the decline in birth rates and total fertility rates.

In the later part of the 20th century, a pioneering group of economists started shaking up their academic field.

These “behavioural economists” used findings from experimental psychology and everyday life to challenge the prevailing view that human beings were rational decision makers – acting in predictable ways to maximize their wealth.

One of those pioneers was Richard Thaler, who noted down some of these “anomalies” in a column in the 1980s, which was turned into a book - The Winner’s Curse - first published in 1992. His work also won him the Nobel memorial prize in economics in 2017.

More than 30 years on, he has returned to that book, publishing a new, updated version with co-author Alex Imas, which looks at whether those anomalies in rational thinking have stood the test of time.

Tim asks him to set out two of his most famous ideas – the winner’s curse itself, and the idea of “mental accounting”.

Presenter: Tim Harford

For months, the share prices of tech companies have marched seemingly-ever upward, driven by fevered excitement about the potential of Artificial Intelligence. But many are now voicing fears that this surge might turn out to be a bubble, which could burst with damaging effects.

So do we have to rely on vibes? Or can we use data to tell us about the risk that AI might go pop?

Nathan Gower discovers what the numbers tell us about the health of the stock market.

Guests:

Presenter and Producer: Nathan Gower

Bernie Sanders says a vast amount of wealth - $50 trillion - has moved from 90% of the population to the wealthiest Americans since the 1970s.

Tim Harford speaks to Carter to understand how he calculated his figures and what they really mean.

If you’ve seen a number in the news you think we should take a look at, email [email protected]

Presenter: Tim Harford

The US Health Secretary Robert F. Kennedy Jr is on a mission to make America healthy again.

Vlad III Dracula, the Wallachian Prince who became Bram Stokers inspiration behind his famous vampire 'Count Dracula,' was a brutal ruler. So brutal that history dubbed him 'Vlad the Impaler' due to his penchant for that particularly gruesome form of execution. Which, without going into too much detail, involved driving a large stake or pole through someone's body - often vertically.

Chroniclers and historians claim that he impaled over 20,000 people during his reigns which, if true is a very, very big number. But is it true? We speak to Historian Dénes Harai whose paper: 'Counting the Stakes: A Reassessment of Vlad III Dracula’s Practice of Collective Impalements in Fifteenth-Century South-eastern Europe' attempts to set the record straight.

Let's travel back to 1431 to separate the math's from the myth.

Presenter/Producer: Lizzy McNeill