Those who have been following lululemon athletica (LULU -1.26%) are no doubt aware of the issues with which the company has been coping. The yoga- and athletic-wear retailer has had to deal not only with consumer concerns over product quality as well as its founder making controversial statements about the company's target consumer, but also with an even bigger problem -- slowing growth. The company had once been growing extremely quickly and was loved by investors on Wall Street. Now, in the face of its slowing growth, the company has seen its shares fall back. However, one division of the company is performing well and may hold the key to the future of its business operations.

Slowing down
While Lululemon has remained very profitable, the simple fact of the matter is that it has seen its revenue growth decelerate in recent years. This has left investors wondering just how quickly the company can actually grow and if it is truly worthy of a premium assessment. Needless to say, the last four years of sales results tell a troubling story:

Financials

2011

2012

2013

2014

Net revenue

$711.7 million

$1.000 billion

$1.37 billion

$1.591 billion

Growth

57%

40.5%

37%

16.13%

Source: Corporate SEC filings.

As you can gather from the information above, Lululemon's revenue growth has fallen dramatically over the last four years. The results even carried over into the first quarter of fiscal 2014, when Lululemon saw its net revenue rise just 11% to $385 million over the year-ago quarter. However, there might be a light at the end of the tunnel.

Direct-to-consumer is picking up the slack
Lululemon is famous for its knowledgeable in-store sales force who often participate in the same yoga classes that new and regular customers find themselves attending. However, in recent quarters it seems that many customers made their workout gear and yoga apparel purchases on the company's website. While the direct-to-consumer division remains relatively small, it still played a part in generating sales for the company. Were it not for this division, Lululemon would have actually seen its sales fall even more in its latest quarter. The results are especially impressive compared to those of Gap, the owner of women's athletic and yoga apparel brand Athleta, which is Lululemon's greatest competitor.

Company

Q1 2013 Online Sales

Q1 2014 Online Sales

Growth

Lululemon

$53.97 million

$65.97 million

22.23%

Gap

$509 million

$575 million

12.97%

Source: Corporate SEC filings.

The chart above seems to indicate that many of Lululemon's customers who have become familiar with the brand and its products are slowly making their way to the company's website to make their purchases. Not only is shopping on the company's website more convenient, it's also easy to use and customer-friendly. In addition to shopping, customers can also learn about upcoming events, take part in live chat, and more. Plus, Lululemon offers free shipping in the U.S. and Canada.

If e-commerce sales continue to rise for Lululemon, it could post higher revenue growth like it did before. While it appears that Gap is also growing its e-commerce business, Lululemon is clearly growing its online sales much faster. This is extremely important for investors who are looking to buy shares of Lululemon, as it means that all may not be lost for the company.

Foolish takeaway
Lululemon's sales growth may be slowing, but the company does have plans to open new stores in the future, and most importantly, its online sales are growing nicely. A major bonus of online sales is that they do not require much of the overhead expenses required by a traditional bricks-and-mortar store. This could very well mean that lululemon's sales and profit may go up as online sales become more important, which almost certainly makes lululemon worthy of a closer look from Foolish investors.