Electric vehicle maker Tesla Inc. (TSLA) is scheduled to report Q3 2019 earnings after the market close on Oct. 23. A key metric that investors should keep in mind when looking at earnings is vehicles delivered. Tesla reported vehicle deliveries earlier this month, and they were up nearly 39% from the same period of 2018.

In the last year, Tesla's stock price has fallen by 0.6%. By comparison, the S&P 500 has gained 8%. For Q2 2019, Tesla reported that revenue was up by 58.7% year-over-year, and earnings per share (EPS) losses were 45.3% smaller.

Tesla and S&P 500 1-Year Returns
Source: TradingView.

However, that Q2 revenue figure was 1.4% lower than the consensus estimate, while the company's loss was 182% larger than the consensus expected. Tesla's earnings report was released after the close on July 24, and the stock declined by 13.6% on the following day.

Tesla has been increasing quarterly revenue steadily since the start of 2016, with the Q2 2019 figure almost exactly 5 times greater than sales in Q1 2016. However, the company has yet to become consistently profitable. After posting positive net income and EPS in the last two quarters of 2018, the only profitable reporting periods in its history, Tesla has again reverted to losing money in 2019.

Tesla Earnings For Q3 2019
  Q3 2017 Actual Q3 2018 Actual Q3 2019 Estimate
Earnings Per Share -$2.04 -$4.22 -$1.35
Revenue $2.790 billion $4.002 billion $6.513 billion
Vehicles Delivered 26,150 83,500 97,000 (actual)
Sources: YCharts, Tesla Investor Relations

Vehicles delivered is a critical metric because sales revenue is only fully realized when the customer can take delivery of a vehicle that he or she has ordered from Tesla. The good news for Tesla is that demand for its products remains strong. In recent years, however, production bottlenecks limited the company's ability to meet that demand.

Today, many of those production problems appear to have been resolved, but distribution now appears to have become the critical limiting factor for Tesla, as reported by the International Business Times. Demand is growing for Tesla vehicles outside the U.S., particularly in Europe and China. In Europe, Norway, Sweden, and Germany are leading markets. China, meanwhile, is Tesla's largest overseas market overall. The Chinese government is in the midst of strong push to reduce air pollution by promoting the use of electric vehicles (EVs), with a goal of seeing annual EV vehicle purchases reach two million by 2020, per the IBT.

Tesla's report that 97,000 vehicles were delivered in Q3 2019 represents a 1.9% improvement over the figure of 95,200 delivered in Q2 2019. The Q2 figure was released after the close on July 2, spurring a 4.6% jump in the stock price on the next day. However, as noted above, a much bigger than expected loss sent the stock tumbling on July 25. The net result was that Tesla ended trading on July 25 a slim 1.9% above its close on July 2.