Ballard Power took a big hit following its earnings report. Photo: Ballard Power Systems.

The stock market has calmed down considerably in recent days, stepping off the roller-coaster it had ridden through much of January and February as investors ponder whether the market can keep advancing into record territory. Economic data showing a 0.7% drop in consumer prices and a rebound in durable-goods orders gave a mixed view of the U.S. economy, and as earnings season starts to wind down, investors appeared ready to pause and take stock of their gains during the early part of 2015. Both the Dow Jones Industrials (^DJI 0.69%) and the broader S&P 500 were flat as of 12:45 p.m. EST.

Yet a few companies still have earnings left to report, and this morning, Ballard Power Systems (BLDP 1.16%) and TASER (AXON 2.64%) were among those that saw negative news hit their share prices hard.

Ballard Power fell 10% after reporting a fourth-quarter loss last night that was larger than investors had expected. Revenue for the clean-energy products specialist dropped 10% from the year-ago quarter, and Ballard saw adjusted operating losses of $16.1 million, resulting in a net loss of $0.13 per share. Ballard has seen a big drop in shipments of its ElectraGen-ME systems for telecom backup power services, and the company's sales from its development-stage markets segment dropped 39% as revenue from its relationships with bus-transit customers declined. Bullish investors highlight the surge in engineering-services revenue stemming from the company's contract with automaker Volkswagen, which Ballard recently extended through 2019. Until Ballard can achieve sustainable profitability, the stock is likely to remain volatile.

Source: TASER.

Meanwhile, TASER dropped 14% despite reporting record quarterly sales. The stun-gun maker announced net revenue of $46.8 million, up 17% from the year-ago period, with sales of its X26P smart-weapon and cartridges helping to fuel the gains. Yet margins fell sharply, and as a result, TASER only posted earnings of $0.09 per share, down a penny from last year's fourth-quarter figures and $0.02 per share less than investors had expected to see. In an effort to diversify its business, TASER is also emphasizing its video capability, providing law enforcement officers with on-body video cameras to gather evidence and document incidents. Yet with its substantial investments in research and development, TASER will have to work harder to ensure that greater sales lead to higher profits in the future.

The stock market still has plenty of uncertainty hanging over it, with geopolitical and global economic issues remaining unpredictable. For now, though, investors seem content to bring February to a quiet close, and individual stock stories will likely dominate market participants' attention for the remainder of the week.