1 April 1999: The minimum wage is introduced in Britain

The first wage laws weren't about how little you could pay your workers, they were about how much. During the reign of King Edward III, in the 1350s, the Black Death had decimated the population. That meant there were fewer serfs to till the fields and grind the corn.

By the age-old rules of the free market, if there's less of something, you have to pay more for it. But of course, this was medieval England and there wasn't a free market. (Some would argue there still isn't, thanks to central bankers.)

So, when on 1 April 1999, Britain's first minimum wage became law under the National Minimum Wage Act 1998, the low-paid descendants of the till hands and field labourers could be forgiven for thinking it was some cruel April Fool's jape. Thankfully, it wasn't. New Labour, with Tony Blair at the helm, pledged to introduce a minimum wage if they were elected in 1997 and elected they were.

Of course, those wealthy medieval barons have their descendants too, and not everyone was thrilled at the idea of a floor dictating how little they could pay their workers. A national minimum wage, it was argued, would destroy jobs and harm those it was intended to help.

As it turned out, the pay floor didn't cost many jobs. Author Tim Harford, writing in the FT, offers by way of an explanation for the "puzzling suspension of the law of supply and demand" that higher wages made for a more committed workforce. Those who have ever been paid the minimum wage may question the wisdom of that.

Nevertheless, when the minimum wage was introduced in the final year of the 20th century, 1.9 million people received a pay rise to £3.60 an hour (£3.00 for those aged 18 to 20). The Low Pay Commission was set up to enforce the new rules.

The rate now stands at a dizzying £8.91 an hour for those aged 23 and over, £6.56 for those between 18 and 20 and £4.62 for those under 18. Apprentices get £4.30 an hour.