For investors following electric-car maker Tesla Motors (NASDAQ:TSLA), the company just announced a date for its fourth-quarter earnings release: February 10. The update will be an important one for investors. Known for its exhaustive shareholder letters and Tesla CEO Elon Musk's extra long question-and-answer sessions, the company's quarterly earnings reports offer investors a way to learn a great deal about the automaker's current operations and its future plans.

Here are some important items to watch when Tesla reports results later this month.

April

Tesla store and service center. Image source: Tesla Motors.

Deliveries by market
Tesla has already reported its deliveries for the quarter. Shipments jumped 50% from the prior quarter and 77% from the year-ago quarter. But if Tesla provides an end-of-the-year update consistent with the way it did in its fourth-quarter report for 2014, the electric-car maker may also provide data on sales for broad geographic segments.

In Tesla's 2014 fourth-quarter update, here's how the sales broke down: 

Metric

North America

Europe

Asia/Pacific

2014 Deliveries (%)

55%

30%

15%

2014 Deliveries

17,400

9,500

4,750

If Tesla provides deliveries by market again in its fourth-quarter letter to shareholders, investors can size up where the company's growth is coming from.

In its most recent shareholder letter, management did provide some context for its Model S orders, which notably differs from shipments, on a market-by-market basis.

"In Q3, global Model S orders increased by more than 50% from a year ago, and grew at a faster pace in North America, Europe and Asia, than during Q2," the company said. While this is vague data, it at least suggests that each market is still growing.

Guidance
Tesla's guidance for vehicle deliveries will be particularly interesting. Its shipments in 2013, 2014, and 2015, respectively, were about 22,500, 31,700, and 50,500. Can the company keep up its extraordinary growth?

Tesla has already provided some context for the year, saying in its third-quarter shareholder letter that it was "highly confident" of achieving "average production and deliveries of 1,600 to 1,800 vehicles per week for Model S and Model X combined during 2016." Converted to guidance for full-year vehicle deliveries, this would equal expectations for 83,200 to 93,600 vehicles during the year, representing significant growth. Will Tesla guide for this range of vehicle deliveries for 2016?

Model X Falcon Wing Doors Inside

Inside Model X with Falcon Wing doors open. Image source: Tesla Motors.

With the company's Model X SUV only beginning to ramp-up production in the last few weeks of 2015, Tesla is counting on the X, along with the vehicle's huge backlog of deposit-backed reservations, to help drive growth for the company during 2016.

Model 3
Finally, investors will look for any commentary on the company's planned Model 3, or its first fully electric car aimed at the mass market. With Tesla saying the car will have a starting price of around $35,000 before any incentives, the Model 3 is crucial to the company's growth plans.

The most recent timeline the company offered for the vehicle's roadmap expectations were for a March unveiling of the car's design and the first shipments by late 2017. Investors will find out on February 10 whether or not the company is still on track with this roadmap for the important car.

Ultimately, it will likely be the company's forward-looking comments that investors will be most interested in when the company reports fourth-quarter results, as Tesla's stock trades at a premium in expectation of management's plans to grow sales from 50,000 vehicles per year in 2015 to 500,000 vehicles per year in 2020.

Daniel Sparks owns shares of Tesla Motors. The Motley Fool owns shares of and recommends Tesla Motors. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.