On Thursday, Swedish fast-fashion powerhouse H&M launched its 11th designer collaboration, this time with French haute couture house Balmain.

Buzz for this partnership has been building for months, thanks in part to the new appeal of once-stuffy Balmain with millennial shoppers.

The brand’s creative director Olivier Rousteing is only 30 years old. His Instagram feed is populated with shots of supermodel friends like Kendall Jenner and Gigi Hadid, both of whom walked the runway for the capsule collection (and both of whom command a rabid social media following).

The #HMBalmainNation launch has already prompted a frenzy, with police having to calm a scuffle outside a London H&M store. A microsite created for the collection crashed almost immediately when it went live at 8am EST.

However, data from past limited-edition designer collaborations — both with H&M and other retailers — shows that those who braved an all-night line or an early morning e-commerce spree may have made a worthwhile investment.

Online and mobile women’s fashion marketplace Tradesy ran the numbers on previous capsule collections that generated the same sort of hype as H&M x Balmain:

– Alexander Wang x H&M
During the height of the this particular frenzy last November, items went for 3 to 5 times the retail price. Today, a year later, pieces from the collection still go for close to double. The average retail price for this line was $85, and the average sale price on Tradesy today is $150.

– Lily Pulitzer for Target TGT -1.30%

The average retail price for this hugely popular spring 2015 collaboration is $32. The average sale price on Tradesy today is $55. During the peak of this sale, Tradesy buyers would land on the Lilly Pulitzer brand page and end up buying from the regular, high-end line. The online marketplace saw overall Lilly Pulitzer sales — not just Target collection items — go up during the launch of this collection.

– 3.1 Philip Lim for Target

The average retail price for this 2013 line was $47. Today, the average sale price on Tradesy is $77 . Even over two years later, prices have stayed higher than retail because most of the items listed are handbags, which hold value. Some items still have a mark up of over 300%.

By noon on Thursday, almost every item of the H&M x Balmain had sold out, and Tradesy was already seeing resellers posting their wares. A $299 cocktail dress from the collection is listed for more than $4,200.

Tradesy founder and CEO Tracy DiNunzio noted that a bold, patterned dress worn on the runway by It Girl model Gigi Hadid has been the most popular item of the day so far.

“Her dress was our first sale, and it went for $1,177.50 when it was originally $649,” she said. “When you combine the Kardashian-Jenners, supermodels and Balmain, you have the makings of a huge hit.”

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