Heard of the Men's Underwear Index? It's the theory that sales in men's underwear are a good indicator of changes in the economy, said to have been created in the late 20th century by American banker Alan Greenspan when he was head of the Federal Reserve.

In theory the MUI could apply now, but Covid-19 has added a whole new dimension when it comes to men's underwear retail, especially online sales at Deadgoodundies.com.

Pants aren't actually down much at all at DGU, in fact several categories are gaining strength as the lockdown continues. Deadgoodundies partner Adam Davies explains: "Men's underwear sales, boxers and briefs, are supposed to echo the state of the nation's spending but the coronavirus crisis has created a very different market, temporarily for sure but possibly also long term."

With menswear shops closed and supermarket shopping diverted to essential supplies like food, men who have traditionally purchased in store (personally or via their partner) have to go without or go online.

"Deadgoodundies' sales of Y-Fronts and men's boxer shorts and trunks, for example, have shot up. Both are always steady sellers, especially in 2 pack and 3 packs, and their faithful fans are now buying online, many for the first time," said Adam.

"On the other hand, we're seeing a lot of new customers coming to DGU and treating themselves to male thongs and men's sexy underwear. Quite why, we can guess, but as we're always discreet with clients' privacy, we don't ask and never tell."

The sales picture at DGU has changed gradually since the UK lockdown started, and Adam is pleased it has mostly settled back to 'normal', with days of much higher sales.

"One thing I have noticed, apart from lots of new customers signing up to Deadgoodundies.com and our newsletter, is the time when men are ordering online. The wee small hours, especially at the weekend, was always a spike but that has been replaced by a 9am flurry."

"I also think a lot of men are unused to buying their own underpants – and relishing the opportunity once they get into it – while many are not used to buying on the internet. What they find is masses more choice than in stores, and on Deadgoodundies.com there are classic and fashion brands from all over the world, some they know, some totally new to them. And as men can receive totally incognito parcels from DGU, they're often being a bit more adventurous with their selection! Men's string underwear is selling like hot cakes…"

And while Adam does not have any concern that Deadgoodundies might run out of boxers and briefs for men, or the male swimwear lines it stocks all year, there might be shortages of some favourite styles of bikini, short, jockstrap or body, and maybe some multipacks, in the coming months.

"We have thousands of pairs of pants in our warehouse and continue to order regularly from our suppliers. So far only one brand cannot deliver at all and others are pushing back delivery dates for some summer and autumn fashion collections. But we stock our brands in a depth and breadth it's hard to find anywhere else in the world, never mind the UK, so there are always alternatives."

Quite how the economists might analyse the new sales pattern is a question for the future and the bean counters – or should that be underpants counters?

Meantime, Deadgoodundies continues to ship virtually as normal – with only two significant changes. The weekday deadline for same day shipping of orders is now 11am instead of 4pm, and customers are asked to be patient as deliveries are, understandably, taking longer than usual to arrive.

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