There's been a lot of investor excitement about electric vehicle (EV) companies. And gains from some stocks have been exceptional over the last two years. Now, the landscape for the sector seems to be clearing so investors can get a better idea of who the players are, and over what time frame EV makers will be bringing out new offerings.

Beyond just looking at the exciting new products and potentially huge market, investors should research details that will help compare and contrast the EV makers. If you're interested in diving in now, the three charts below will provide a look at some data worth considering before you make an investment.

A translucent electric car set among green leaves and trees.

Image source: Getty Images.

Returns have been unpredictable

Many have bought into the EV sector looking for large, market-beating returns. While shares of EV leader Tesla (TSLA -0.32%) skyrocketed last year, as the field of publicly traded names has grown, returns have been inconsistent. And investors need to be prepared for plenty of volatility along the way. The chart below shows the most recent six-month returns from a mix of U.S.- and China-based EV makers:

NIO Chart

Data by YCharts.

Even the strong returns from Tesla and Lucid Group (LCID 1.84%) stocks have included big swings in just the past two months. And though Chinese EV makers Nio (NIO 8.72%) and XPeng (XPEV 11.16%) have been growing sales quickly, their stocks have backtracked since June 2021. Lordstown Motors (RIDE -1.13%), maker of the Endurance all-electric work truck, has struggled, and shareholders have paid the price this year. The lesson is that there will be winners and losers, and EV stock moves can be quick and extreme.

There's plenty of demand

Just looking at share-price movement doesn't tell the full story, of course. While Nio and XPeng shares haven't moved higher in the last half-year, both company's sales skyrocketed over the first nine months of 2021, as shown below:

Bar graph of nine-month vehicle delivery increase for Tesla, Xpeng, and Nio.

Data source: Company financial filings. Chart by author.

*XPeng 2021 comparison with final three quarters of 2020.

Tesla has almost doubled its deliveries over the first nine months of 2021 compared to the year-ago period. But XPeng and Nio deliveries are growing much faster, though the two Chinese companies are growing off of a much smaller base. And as both are already richly valued, with recent market capitalizations of around $36 billion and $48 billion, respectively, investors have sold off shares in recent months. Global demand is strong and growing, but that won't automatically result in growing share prices.

Profitability will take time

Investors in any business need to focus on the bottom line. Early stage growth companies aren't necessarily expected to become profitable quickly, however. Especially with a high-fixed-cost business like automotive manufacturing, profits will only come with scale. As the chart below shows, few EV makers are bringing in profits yet:

bar graph showing Q3 revenue and profit/loss for Nio, XPeng, BYD, Tesla, Rivian, and Lucid.

Data source: Company financial filings. Chart by author.

Tesla led the industry with a reported profit of more than $1.6 billion in the third quarter of 2021 .

BYD is perhaps a less well-known Chinese EV company, and it sells more than just electric cars; it also makes batteries, electric buses, and traditional internal combustion vehicles. But its "new energy vehicles" -- which include plug-in hybrid electrics -- made up more than 90% of the nearly 100,000 new energy passenger vehicles it delivered in November.

Lucid and Rivian Automotive (RIVN 5.22%) are getting a lot of attention recently, but they've barely started shipping product; the losses there will continue for some time until those companies reach scale. Investors hope that Nio and XPeng reach profitability soon, as both are growing sales and expanding product offerings. But investors interested in the sector need to be prepared for a long road before profitability can be expected.