The IPO market is about to face its biggest test of the year

Two of the biggest initial public offerings to hit Wall Street this year are pricing their shares Wednesday night.

They could make or break the IPO market for the rest of 2015.

Neither of these deals is terribly exciting, but they're both big. First Data, a global payments processor, is looking to raise nearly $4 billion, and plans to use the money to repay debt. Albertsons, the supermarket chain, is asking investors for almost $2 billion.

Neither company is incredibly exciting either, but they are both leaders in their respective markets. So if they're successful they could ease the way for other companies looking to tap investor demand.

"If this new IPO class is received well by the market, it should create a virtuous circle of confidence, and bring other issuers out of the woodwork," said Jeffrey Nassof, vice president of consulting services at Freeman & Co.

The IPO market could use a boost right about now. Proceeds raised in US IPOs are down more than 44% from last year, and the number of deals is down by about 20%, according to Renaissance Capital, which analyzes initial public offerings.

And its not just that there's been a dearth of offerings. If the market isn't receptive to newly listed shares, that could discourage IPO investors looking for a quick profit.

Last week, flash-storage provider Pure Storage fell in its trading debut ending its first day of trading below its private market valuation.

"When you price things very aggressively in the private market, it's not rational to expect them to pop in the public market," said Lise Buyer, an IPO consultant with Class V Group in Silicon Valley .

She's reluctant to call Pure Storage's IPO bad news for the tech sector. It did, after all, raise more than $400 million in new capital - but is equally unsure that other tech IPOs will come flowing down the pipeline this year.

Here's what's on schedule for this week, and beyond: