Around 10 million people in Britain smoke cigarettes, according to the latest available statistics. But as every smoker knows, it's an expensive habit, with a pack of 20 now costing more than a fiver.
How did they come about these figures? it's complicated, and you need an understanding of statistics to get to the bottom of it. But to give you an idea, the researchers claim their estimate is based on a measurement used by economists called the value of a statistical life.
It's all highly theoretical, but the average amount of money someone in Europe is prepared to pay to reduce their risk of death is £2.53 million, the experts argue. But if you're a smoker, that cost rises to £3.29 million. And from that, the Spanish researchers claim to have calculated the true cost of a pack of cigarettes, based on the average amount people smoke during their lifetime.
Well, we said it was complicated.
But it gets worse. These figures don't take into account the cost of any healthcare required, should you develop a smoking-related disease. They're just an estimation of the cost borne by smokers themselves.
What's your opinion on the price of cigarettes? If they were more expensive, do you think more smokers would quit?