COPENHAGEN (Reuters) – Nets NETStemp.CO, issuer of Denmark’s most used debit card, was valued at 30 billion Danish crowns ($4.5 billion) in its listing on Friday, nearly double what Advent International, Bain Capital and pension fund ATP paid for it two years ago.

Demand for shares in Scandinavia’s largest payments processor exceeded expectations and the initial public offering (IPO) was four days earlier than planned.

Nets’ listing is one of just a handful of IPOs in the European tech sector this year after a slump and other firms are watching to see if prices hold up enough to justify pushing ahead with their own IPOs.

Dutch online food ordering firm Takeaway.com plans to list on its home market this month, while Spanish mobile phone tower business Telxius and German online pharmacy Shop Apotheke Europe are eyeing IPOs in October.

British payments processor Worldpay Group WPG.L was listed on the London Stock Exchange in October last year with a valuation of 4.8 billion pounds ($6.34 billion).

Shares in Nets opened by as much as 3.3 percent above the offer price of 150 crowns, but had fallen to 148.90 by 0949 GMT.

Nets said 36.7 million new shares will be issued, raising gross proceeds of 5.5 billion Danish crowns, while existing shareholders, including private equity firms Advent International and Bain Capital, sold 68.3 million shares.

An IPO has been on the table since its 17 billion Danish crown acquisition by Advent, Bain Capital and Denmark’s ATP in March 2014.

Nets is seen by some investors as more of a long-term investment than a fast IPO return case, Jyske Bank analyst Michael Jorgensen said, with its “story” one of Nordic economic stability and a technological width not seen in its peers.

The firm’s chief financial officer Klaus Pedersen called the IPO a success, but said competition in the industry was intense.

“Our advantage is that we have a wide range of products covering pretty much all payment solutions, and we have scale and volume that gives us low unit costs. That is where start-up fintech companies meet challenges,” Pedersen told Reuters.

He expects Nets to grow revenue organically by about 6 percent this year and by 5-6 percent in the following three years. That compares against an industry that is expected to grow by 4 percent per year until 2020, he said.

Approximately 42,000 new shareholders have been allocated shares and Nets said an overallotment option of an additional 15.75 existing shares could bring the total offering size to as much as 18.11 billion Danish crowns.

The company’s free float will be between 52 percent and 60 percent, depending on the overallotment size.

Deutsche Bank, Morgan Stanley and Nordea were joint global co-ordinators and joint bookrunners for the IPO.

Nets said earnings before interest, tax, depreciation and amortization before special items (EBITDA) rose 13 percent to 1.2 billion Danish crowns in the first six months of 2016 corresponding to an EBITDA margin of 33.4 percent.

Nets wants to lift this to 35 percent this year from 32.9 percent last year, and aims to increase it to the “high 30s” over the next three years.

The company is likely to enter the Danish leading index OMXC20 with the 20 largest and most actively traded shares on Nasdaq Copenhagen when it is revised in December, Jyske Bank’s Jorgensen said.