By Carolyn Enting*
As Birkenstock footwear celebrates its 250-year anniversary, a Wellington retailer has created an Excel spreadsheet to record the number of lost Birkenstock sales per annum.
The Last Footwear Company on Cuba Street, which has been stocking the German brand since the '80s, can't get enough of them. Now when someone comes into the store wanting a pair they don't have, the phantom sale is recorded.
"I hate to think of how many sales we've missed over the years because we couldn't get the stock," says general manager Clint Johns.
He estimates it would be at least 1500 pairs. The thinking behind the spreadsheet, aside from curbing their curiosity, is to try and help forecast what styles to order and in what sizes, so they are better prepared for the next season, if they can get them.
"People think you're making up stories when we say we can't get the stock but there's a worldwide shortage. It's not just a New Zealand thing," says Johns.
"Last year we had real difficulty getting certain sizes. They can't make enough of them."
Deconstructing the hype
So how did such a "fugly" shoe become so coveted? It's a complicated blend of factors. Ironically, it was designer Phoebe Philo's "Furkenstocks" - fur-lined Birkenstock-inspired sandals - for Céline's 2013 collection that helped them become truly fashionable.
Givenchy then produced floral and metallic versions of the Arizona sandal in 2014, retailing for up to NZ$1278 (£595). The original Birkenstocks, which were much more accessible, enjoyed knock-on success.
Celebs, including Gigi Hadid and Charlize Theron, were papped everywhere in Arizona sandals. They're still in vogue - Johns says the tan 'Havana' colourway is currently "almost in a rationing situation".
Birkenstock confirms that the Arizona, which got another boost last year thanks to the Barbie movie, is still the most popular silhouette. Film director Greta Gerwig has said it wasn't a paid product placement, but the pink two-strap sandal's cameo drove an 1800 percent sales increase for the brand.
Why so expensive?
In recent times the price of Birkenstocks has risen 30 to 40 percent, which is a fair chunk on something that's already top of the range.
"Prices have been going up so much, yet we see young girls coming in and not even flinching and spending $300 on a pair of sandals," says Janssen.
Birkenstock global head office pointed out "all shoes are made in Germany from high quality natural materials mainly from Europe and produced over six production sites spread across the country".
While being made in Germany hinders the company's ability to meet increased demand, it's proved to be a winning formula.
"Scarcity breeds excitement on the part of the consumer and that's been part of the winning strategy for them," Matt Powell, NPD Group senior industry advisor for sports told CNBC Make It.
Short long history
Recently, in the lead up to the brand's big birthday, a team of international experts went through private and public archives and personal estates to prove Birkenstock's heritage and put its rich history on factual ground.
It can be traced back to shoemaker Johannes Birkenstock who gets a mention in a 1774 German church archive document (five years after Captain James Cook reached New Zealand's shores). The name is unmistakable, written in the cursive writing of the time.
Birkenstock's journey to achieving style status has been a slow burn.
Konrad Birkenstock (born 1873) - the great-grandson of Johann Adam Birkenstock (born in 1754) - turned to orthopaedics and developed the first anatomically shaped last in 1902. His son Carl Birkenstock developed his ideas further, a handmade shoe based on the principle of "walking as nature intended" in 1936.
Then Carl's son (Karl with a K), joined the company in 1954. He continued to develop his ancestors' ideas on foot health and natural walking, coming up with a standardised insole that he based on the average of all the feet he measured. The cork-latex footbed as we know it today was born.
Karl took inspiration for his shoe designs from modern architecture, though the avant-garde modernity of his sandal was not accepted by the mainstream. When introduced at the Düsseldorf shoe fair in 1963, it was an utter flop.
*Carolyn Enting is a freelance lifestyle and fashion writer.
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