Though Tesla (NASDAQ:TSLA) has already announced how many vehicles it delivered in its second quarter, the company's financial performance during the period is still a big mystery. Sure, the electric-car maker delivered more vehicles than in any quarter in its history. But this doesn't mean it performed well financially during the period. Indeed, the average analyst estimate calls for negative non-GAAP (adjusted) earnings per share of $0.52.

Investors, however, will get a better feel for Tesla's second-quarter performance soon. The company just scheduled its earnings report for after market close on Wednesday, July 24. Investors will be looking for insight into a range of key items, including free cash flow, gross profit margin, management's full-year outlook for vehicle deliveries, and more.

Here's a preview of what to expect from some of these metrics.

Tesla's Model S, 3, X, and Y

Image source: Tesla.

Free cash flow

Tesla's profitability in the second half of 2018 was short-lived. After posting positive free cash flow of $881 million and $910 million  in the third and fourth quarter of last year, respectively, the important profitability metric plummeted in Q1. Free cash flow during the period was negative $920 million as Tesla's overseas expansion of Model 3 deliveries during the period proved costly.

For the second quarter, management said it expected to return to positive free cash flow, but it won't be until Q3 that the company expects to have positive net income.

Automotive gross margin

As deliveries fell sequentially in Q1, Tesla's automotive gross margin declined, falling from 24.3% in the fourth quarter of 2018 to 20.2%. This metric should see improvement in Q2, though, thanks to record deliveries during the quarter. Tesla delivered 95,200 vehicles in Q2, driven by soaring Model 3 deliveries.

While Tesla didn't provide any specific guidance for its second-quarter gross margin, management did say in its first-quarter shareholder letter that it continues "to target a 25% non-GAAP gross margin on Model S, Model X and Model 3, depending on variant mix and option take rates as our product offerings change."

Full-year outlook

Finally, investors will want to look to see whether Tesla maintains its full-year outlook for vehicle deliveries.

Going into 2019, the automaker said it expected to deliver 360,000 to 400,000 vehicles this year, representing 45% to 65% year-over-year growth. Despite delivering fewer-than-expected vehicles in Q1, Tesla reiterated its this outlook in its first-quarter shareholder letter. With half of the year in the rearview mirror, will Tesla maintain this forecast again?

Since second-quarter deliveries of over 95,000 vehicles were slightly above the midpoint of management's 90,000-100,000 forecast, it will likely stick to its guidance once again.

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