9 mind-blowing facts about the United Kingdom's economy

When you think of the UK you might think of rolling green hills covered by placid flocks of grazing sheep. But offshore oil rigs and Brent crude are also a big part of the UK economy.

Petroleum exports were worth $17.8 billion in 2018, according to the Observatory for Economic Complexity at MIT. The CIA's World Factbook lists the UK as the 21st largest producer of crude oil, with estimated production of 933,000 barrels a day in 2016.

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Since the Brexit referendum in June 2016, the pound has fallen 14% versus the US dollar, though the British currency has partially rebounded on several occasions. The BBC reported that UK households have each effectively lost 900 pounds, or about $1,140, because of the currency turmoil surrounding Brexit.

As damaging as Brexit has been to the UK pound, the damage to the British economy could get worse. If the UK leaves the EU without a negotiated deal (a so-called no-deal Brexit), the nation's GDP could plummet 8% and unemployment might rise to 7.5%, according to Bank of England projections. The Organization for Economic Cooperation and Development has echoed this prediction.

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The UK had 145 billionaires in 2018, making it the country with the fifth most billionaires in the world. The UK has a population of 67 million, meaning one out of every 462,000 or so Britons is a billionaire. That's about the same rate as the US, where one out of every 466,000 or so Americans is a billionaire.

There is plenty of old money in the UK — very old money. According to Architectural Digest, Buckingham Palace, home to the British royal family, is the world's most expensive home, valued at $1.55 billion. CNBC estimated the net worth of the royal family at $1 trillion, second only to Saudi Arabia's House of Saud monarchs.

If your means are more modest, you still might be able to afford your own private island in the UK.

The Island of Linga, off the coast of Shetland, is for sale for about $351,000. The Shetland Islands are the most northern outpost of the UK, closer to Norway than Scotland. The purchase price for Linga includes a loch and building permits but no complete structures. The island's two stone cottages stand roofless, so consider this isle a fixer-upper.

The National Health Service (NHS) provides free healthcare across the UK. It also provides jobs – a lot of jobs. Forbes ranked the NHS as the fifth largest employer in the world, with 1.5 million employees.

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Before you grumble about paying 10% tax on your next purchase at a US store, consider the UK's VAT (value added tax). The tax is 20% on most goods and services. Unlike in the US, UK businesses must include VAT in the price, so you might not notice the charge.

Compare this to the US, which has a patchwork of tax rates that top out at 11.5% in Oklahoma City.

But amazingly, Britian's VAT is not among the highest in the world. Iceland, Greece, Norway, Finland, Sweden, Denmark, and Croatia impose VATs that top out between 24 and 25%. And India adds a sales tax of 28% to some luxury products.

In the UK, books, magazines, newspapers, and other publications are excluded from VAT.