Eyeglass brand Warby Parker has lost money or broken even over each of the past three fiscal years — and warned it may face headwinds as it tries to turn a profit as a public company, according to documents filed with securities regulators on Tuesday.

The retailer, which is best known for selling lower-priced, fashion-forward prescription glasses, is preparing to debut on Wall Street. It said in January that it had confidentially filed for a stock market listing in the U.S.

With its initial public offering, Warby Parker is expected to join a growing list of consumer-facing brands that will be trading soon on Wall Street. Jessica Alba’s Honest Co. and medical scrubs-maker Figs recently went public. Salad chain Sweetgreen filed confidentially for an IPO and shoe brand Allbirds is reportedly getting ready for one, too.

Over the past three years, Warby Parker’s sales have grown — but so have its losses. Warby Parker’s net revenue in the fiscal years that ended Dec. 31 of 2018, 2019 and 2020 were $272.9 million, $370.5 million, and $393.7 million, respectively, according to documents filed with the U.S. Securities and Exchange Commission.

Its net loss was $22.9 million in 2018 and $55.9 million in 2020. It broke even in 2019, the company told regulators.

Warby Parker said it has continued to lose money in recent months. It lost $7.3 million in the six months ended June 20. As of that date, the company had an accumulated deficit of $356.3 million.

“Because we have a short operating history at scale, it is difficult for us to predict our future operating results,” the company said in the filing. “We will need to generate and sustain increased revenue and manage our costs to achieve profitability. Even if we do, we may not be able to sustain or increase our profitability.”

The start-up has won the confidence of heavy-hitters in Silicon Valley. It raised $120 million in its most recent round of venture funding in 2020, which gave it a value of $3 billion, according to PitchBook data.

Its stockholders will include some of those investors, Tiger Global, T. Rowe Price, General Catalyst, D1 Capital Partners and Durable Capital, according to the filing