Wendy's
Wendy's pretzel burger has been a success in test markets and could make its national debut later this year. Reuters

Wendy's has officially taken over as second biggest hamburger chain in the United States from its rival, Burger King.

Wendy's $8.5 billion sales in 2011 edged past Burger King's $8.4 billion, according to the Associated Press. However, both companies fall way below the number one burger spot, McDonald's which saw $34.2 billion in sales for 2011, reported the Associated Press.

These figures are reportedly based on Technomic's estimates of system-wide sales comparing franchise owned and company-owned restaurants, rather than only looking at corporate revenue which includes franchise operator fees. Technomic Inc. is a research firm that compiles and releases data on the food industry.

However, the data also shows that Burger still has many more restaurants than Wendy's. Under that spectrum, it still remains the second biggest hamburger chain behind McDonald's, reported the AP.

Both Burger King and Wendy's have had difficulty keeping up with the McDonald's in recent years. However, this has helped the consumer because this kept prices low throughout the recession while introducing new fast food items to the menu.

In the past five years, McDonald's saw sales increase rise 26 percent, Wendy's increased 9 percent and Burger King's sales remained stagnant, reported the AP.

Wendy's has also been attempting to reinvent itself to a higher-end hamburger chain, reported the AP. The introduction of Dave's Hot 'N Juicy burger last fall has been the first step in accomplishing this goal.

While Wendy's is the number 2 hamburger chain, it lags behind as the largest restaurant chain. Subway is now No. 2 with $11.4 billion in sales. Starbucks is No. 3 with $9.8 billion in sales in 20011. The U.S. sales for both of these companies are growing much faster than the hamburger chains, reported the AP. Subway's sales are up 48 percent and Starbucks sales are up 39 percent from five years ago.