What happened 

Shares of Proterra (PTRA), an electric bus maker and electric vehicle (EV) tech company, were plummeting today after the company reported fourth-quarter results that missed both top- and bottom-line consensus estimates. Additionally, the company issued weak guidance for the full year. 

As a result, Proterra's stock tumbled 47% as of 12:04 p.m. ET 

So what

Proterra reported revenue of $80 million in the fourth quarter, which was up 17% from the year-ago quarter but missed analysts' consensus estimate of $86.8 million. Additionally, Proterra's loss of $0.50 per share in the quarter was worse than the company's loss of $0.43 in the year-ago quarter and far below Wall Street's consensus estimate of a loss of $0.25 per share. 

The company said in prepared remarks that total operating expenses increased 40% in the fourth quarter to $53.3 million, but it also highlighted the fact that electric bus production will be consolidated at the company's Greenville, South Carolina, facility by the start of the second quarter and battery production from another facility will be consolidated by the end of the third quarter. 

The company hopes the streamlined production will promote operational efficiencies and "improve Proterra's contribution to gross margin by the end of 2023." 

Now what 

Investors weren't impressed with the company's latest financial results and they didn't appear enthusiastic about Proterra's outlook either. The company issued 2023 revenue guidance in the range of $450 million to $500 million, but that guidance fell below Wall Street's consensus estimate of $533.8 million. 

Many EV companies are under pressure right now as high inflation, rising material costs, and increasing competition have weighed on many electric vehicle stocks. With Proterra's latest results and disappointing guidance, investors may need to see several quarters of strong growth from the company before they regain their optimism.