• Lyft reported fourth-quarter earnings after-the-bell on Tuesday.
• Lyft reported 18.73 million active riders in the last quarter of 2021. It's lower than the prior quarter and misses analyst expectations.
• Lyft reported a net loss for the quarter of $258.6 million versus a net loss of $458.2 million in the same period of 2020.

Lyft reported fourth-quarter results after the bell on Tuesday. It beat estimates on adjusted earnings per share and revenue but said it had fewer active riders than in the prior quarter.

Shares were down more than 6% in after hours trading after executives said the omicron coronavirus variant would weigh on first quarter numbers.

Here are the key numbers:

• Earnings per share: 9 cents, adjusted, vs 8 cents expected in a Refinitiv survey of analysts
• Revenue: $970 million vs $940.1 million expected by Refinitiv
• Active riders: 18.73 million vs 20.2 million expected, per StreetAccount
• Revenue per active rider: $51.79 vs $46.54 expected, according to StreetAccount

Lyft reported 18.73 million active riders in the last quarter of 2021, up nearly 50% year-over-year but short of StreetAccount analyst expectations of 20.2 million riders for the quarter. It's a decline from the third quarter when Lyft said it had 18.94 million active riders and not quite back to pre-pandemic levels. Lyft reported 22.9 million active riders in the fourth quarter of 2019, for example.

Lyft is expecting the omicron surge of the Covid-19 pandemic to lower first quarter results in 2022. It expects Q1 revenue between $800 million and $850 million. Analysts expected guidance of $989.9 million, per StreetAccount.

The company didn't provide exact guidance on active rider projections, aside from saying it expects rides to decline slightly quarter-over-quarter. Analysts expect the company to report 21.7 million active riders in the first quarter of 2022, according to StreetAccount guidance.

"Despite short-term headwinds from omicron, we remain optimistic about full-year 2022," Lyft's new CFO Elaine Paul said in a statement. Still, the pace of recovery is uncertain.

Lyft revenue jumped 12% quarter-over-quarter to $969.9 million. That's up 70% year-over-year thanks to easy comparables due to the Covid-19 pandemic. It also noted record revenue per active rider of $51.79, which is up 14% year-over-year.

Lyft reported a net loss for the quarter of $258.6 million versus a net loss of $458.2 million in the same period of 2020. The company said its loss included $164.2 million of stock-based compensation and related payroll tax expenses.

Lyft again posted an adjusted EBITDA (earnings before interest, taxes, depreciation and amortization) profit of $74.7 million. In the prior quarter, Lyft reported adjusted EBITDA of $67.3 million.

The company has struggled with driver supply and demand imbalances throughout the pandemic, leading to higher costs or long wait times.

CEO Logan Green said during the call with investors that Lyft sustained driver recovery in the quarter. Ride ETAs improved by roughly 30% across all of its operating markets. Active drivers hit a new pandemic high, Paul added, who are expected to maintain despite the omicron variant.

Another key marker of recovery, Lyft said airport rides more than doubled in the quarter compared to last year.

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