For those in the know, metrics like a country's GDP, CPI, and PMI can suggest where the economy is heading.

But when it comes to really gauging the health of a nation's economy and predicting its future, experts look at all sorts of obscure and outlandish factors.

From the Big Mac Index to the Sports Illustrated Swimsuit Cover Indicator, read on to discover some of the most peculiar signs of economic fortune or failure. All dollar amounts in US dollars, unless otherwise stated.

The Lipstick Index was thought up in 2001 by Estée Lauder board chairman Leonard Lauder, who had noticed that women tend to spend more on lipstick and other makeup items amid economic downturns.

One of the less reliable quirky indicators (and that's perhaps saying something...), the theory has been disputed in more recent years, particularly during the COVID recession when cosmetics sales tanked.

Nonetheless, a recent upswing in beauty sales in the UK, which is currently undergoing a cost of living crisis, shows the index might still have relevance.

This one is the brainchild of John Paul DeJoria, the founder of the Paul Mitchell hair care brand.

Explaining his theory, DeJoria told Business Insider in 2011 that "beauty salons are the best economic indicator. Typically, customers will visit every six weeks; in downturns that drops to every eight weeks. When it goes up again, things are on the mend".

The Men's Underwear Index (MUI) posits that sales of men's undergarments dip when economic conditions fall.

Former Federal Reserve chairman Alan Greenspan is a big fan of the idea, meaning it's actually taken relatively seriously.

But much like other retail and personal care-related indexes on our list, this indicator was turned on its head during the COVID recession. Sales of men's underwear actually increased thanks to the boom in online shopping.

Another idea reportedly favourited by Alan Greenspan is the Dry Cleaning Index.

When consumer confidence is high and the economy is thriving, dry cleaners report healthy business. The opposite is the case during downturns.

Unlike the MUI, this indicator was spot on during the pandemic, with people trading smart clothes and fancy dry-clean-only party outfits for comfy loungewear.

Also known as the "Bear Knees, Bull Market" index, this indicator was devised way back in 1926 by economist George Taylor and has been bang on the money over the years. 

In 2010, two Dutch researchers analysed monthly hemline data from 1921 to 2009. They found that hemlines do indeed hitch up when the economy is booming and drop back down during times of strife, with a time lag of around three years.

Yet another economic signal that's been uncannily accurate over the decades, the Super Bowl Indicator predicts whether the US stock market will close lower or higher for the year.

If a team from the old American Football League wins, the market will typically end the year lower, while a victory for an erstwhile National Football League team typically precedes a buoyant market at close.

As of 2021, the astonishing indicator has been correct almost 75% of the time over a 53-year period.

PNC Bank's Christmas Price Index is a charming festive tradition that's been going for almost 40 years.

The annual index compares prices year-on-year for each gift mentioned in the popular carol, The Twelve Days of Christmas.

It makes for a fun way to chart inflation and pick out long-term trends, such as the tendency for gold prices to rise during recessions. Though we're not quite sure what the sales of turtle doves and French hens might suggest...

One of the more niche pointers on our list is the Japanese Whisky Indicator, which was put forward by Wells Fargo economist Richard DeKaser in 2019.

Having noticed prices had spiked for the premium booze brands Hibiki and Yamazaki, DeKaser suggested that the hikes were an omen of bad times ahead.

Lo and behold, the Dow Jones promptly plummeted in August of that year and almost the entire world was in recession by the following February. We won't drink to that.

The Cardboard Box Indicator is exactly what it says on the tin (or should that be box?) and suggests that the higher the rate of cardboard box production, the better the economy is faring.

The index is published on the Federal Reserve Bank of St Louis website, and shows that production declined during the Great Recession (December 2007 to June 2009) and COVID downturn.

When conservative news site Drudge Report concentrates on business stories, the US stock market bottoms out.

At least that's what Bespoke Investment Group discovered in 2012 after it compared the frequency of financial-related headlines on the website to the ups and downs of the S&P 500.

The stock market index was found to drastically drop when the number of Drudge Report business stories peaked.

This decidedly macabre idea suggests that the number of corpses that go unclaimed has a tendency to rise when times are difficult. This is due to struggling families being unable to cover funeral costs.

This was most certainly the case during the Great Recession as well as the COVID slowdown, which was further compounded by a massive surge in deaths.

In times of hardship, the sales of baked beans go through the roof as people turn to budget-friendly canned foods in a bid to save money.

During the Great Recession, cans of the kitchen cupboard staple flew off the shelves. Sales spiked even more significantly in 2020 when they increased by a whopping 245% in the US and 72.5% in the UK amid the COVID downturn.

This indicator is based on the idea that US stocks perform better in years when the model gracing the cover of Sports Illustrated's annual swimwear edition is American.

Created in 2000 by Bespoke Investment Group, the index has a decent-enough track record, being broadly correct between 1978 and 2012. However, that's not to say that it hasn't been glaringly wrong on occasion...

Just to confuse matters further, there are four cover models this year: Americans Kim Kardashian, Ciara, and Yumi Nu, and Canadian-South African Maye Musk.

A sagging economy can make even the most image-conscious person decide to postpone their plastic surgery. This is due to the sky-high costs for such procedures, as well as the fear of being fired from work for taking the time off.

In 2008, cosmetic surgery revenue fell 9% in the US. Fast-forward to 2020 and the number of procedures carried out dropped by 14%, which could suggest that this unusual indicator could actually be one of the more reliable.

When the US Marine Corps gets inundated with applications, the grittiness of its recruitment ads is typically dialled up in a bid to deter unsuitable candidates.

A worsening economic situation is one of the key factors behind rising recruitment numbers, meaning that the tone of the ads can be used to gauge how well the economy is doing.

A fear-free campaign denotes things are good, while a more intimidating equivalent suggests times are getting tough.

Dubbed "burgernomics", this fast food-inspired indicator was dreamt up by The Economist in 1986 to determine whether a currency is over- or undervalued.

Now published biannually, the index compares Big Mac prices around the world using purchasing-power parity (PPP).

According to the July 2022 edition of the index, the Swiss franc is the most overvalued currency against the US dollar at +30.3%, while the Romanian leu is the most undervalued at -55.7%.

During a recession, drinking shifts from the bar to the home, with the hard-up cutting down on nights out in favour of cheap supermarket beer instead.

With that in mind, it makes sense that supermarket sales of the most affordable alcoholic drinks noticeably jump when the economy slumps.

According to Chinese astrology, the Year of the Dragon brings good fortune and prosperity. It's fitting, then, that since 1900 the Dow Jones Industrial Average has typically returned 7.7% during dragon years, well above the average of 5.5%.

The last Year of the Dragon was 2012, while the next one is 2024 – and we imagine that there are countless superstitious folk around the globe who are counting down to the momentous occasion.

Investing in a recreational vehicle is a costly commitment that people are less likely to make if they're concerned about the economy.

As it happens, RV shipments fell in the US before the early 1990s recession, the dot-com bubble recession, the Great Recession, and the COVID recession. That's a pretty accurate hit rate...

During economic downturns, dog thefts tend to rise as people become increasingly desperate to get by.

In 2011, the American Kennel Club claimed that the Great Recession had sparked a dognapping crime wave across America.

Similarly, the number of pinched pooches in the UK hit unprecedented levels during the COVID crisis, increasing by 170% between 2019 and 2020.

Unsurprisingly, champagne sales pop when the economy is prospering – and fall flat when fortunes decline.

But what is astounding is how accurate the correlation is. In 2011, NPR's Planet Money revealed that the amount of French fizz that Americans consume can indicate what the average American income will be one year later, with nearly 90% accuracy.

Highlighted by a 2011 IBM study, the High Heel Index works in the opposite way to the aforementioned Hemline Index in that heel heights step up during economic downturns and drop back in boom times.

The idea is that followers of fashion turn to more flamboyant footwear as a means of escapism when the economy falters. Best foot forward and all that...

The Tie Index postulates that sales of ties, particularly of the cheaper synthetic kind, explode in times of economic woe.

The reason? Employees are reportedly keen to smarten up and impress their bosses in a bid to keep their jobs safe.

The index rung true in the UK during the Great Recession when man-made ties were wildly popular – although interestingly, sales in the same period actually fell in the US.

On a related note, this index is based on the idea that ties get skinnier when times are hard. The idea harks back to wartime austerity measures that called for sparing use of fabrics.

Interestingly, slimline ties became all the rage during the Great Recession. In November 2019, three months before the COVID downturn began, Vogue declared the comeback of the fashionable accessory after actor Robert Pattinson wore one on Late Night with Seth Meyers.

invented by New York Magazine writer Hugo Lindgren back in 2009, this oddball idea is based on the assumption that the number of overqualified taxi drivers one encounters will increase during economic downturns.

Lindgren also suggested a couple of other unlikely indicators, including the Squeegee Man Apparition Index – the more of them there are, the worse the economy is – and the Speed at Which Contractors Return Calls Index.

About the latter, he noted: "[if they call back] within 24 hours, you're in a recession; if they call you without prompting, that's a depression".

Staying with ties (who knew they could express so much?), colour trends can also reflect and predict the state of the economy.

In 2009, Robert Allsbrook, the chief economist for Alabama's Regions Bank, revealed in an interview with NBC News that men tend to wear ties in drab hues during downturns and opt for more brightly coloured neckwear when the economy picks up.

In a roundabout way, the Mosquito Bite Indicator can point to a tanking housing market and general sense of economic downturn.

The reasoning behind it is that the number of mosquitos around tends to increase when properties sit empty, with unmaintained pools and overgrown gardens providing the perfect habitat for the critters to multiply.

By way of example, the number of neglected pools treated in Arizona's Maricopa County soared by 60% in 2009 following the housing crash.

Coined by FEMA administrator Craig Fugate in the wake of 2004's Hurricane Charley, the Waffle House Index is used to ascertain the scale of a natural disaster, as well as the level of response required.

The branches of restaurant chain Waffle House have a reputation for often being the last businesses to shut when calamity strikes – meaning that the more closed Waffle Houses there are, the more severe the situation tends to be.

Now discover why the future looks bleak for these major economies