As eyes turn to a potential Spotify public offering next year, the company’s recent financial performance might bolster its case to investors. But questions about profitability remain.

The music streaming service recorded revenue of 1.9 billion euros ($2.2 billion) in the first half of this year, according to two people briefed on the numbers, putting it on pace for about 4.1 billion euros in 2017. That would be about 40% higher than last year’s revenue. Spotify again recorded a significant operating loss, of between 100 million and 200 million euros in the first half of the year, according to one of the people briefed on the numbers, which the company shared with investors. But one important metric of profitability, gross margins, improved.