OAK BROOK, Ill. — McDonald's Corporation (NYSE:MCD) announced on Tuesday that same store sales growth for company and franchised stores open for at least 13 months in the United States missed estimates. Same store sales were up 3.3 percent, down from analysts more lofty expectation of 5.

Known for an almost flawless execution of its initiatives, McDonald's blamed its sales shortfall on the calendar. This year April had one less Friday and Saturday, which it says are big sales days, and one more Sunday and Monday compared to 2011. The company explained that the resulting adjustment varied by the area of the world, ranging from a drop in sales by approximately -2.3% to -0.9%.

Competition heats up: Burger King eats into McDonald's

McDonald's competitors also had the disadvantage of a month with fewer Fridays and Saturdays. Wendy's saw its same store sales rise by 0.8 percent in the first quarter of this year. Among other things, the brand is still recovering from an earlier misstep. In an earnings call on Tuesday, the new chief executive officer of the chain said that it had clearly made a mistake in pricing the new beefier $2.99 "W" burger lower than its less meaty $3.49 Dave's Hot 'N Juicy. The former leadership had hoped to entice 99 cent shoppers to upgrade to the new, more expensive "W" burger. Instead, the mid-priced "W" burger cannibalized its premium Dave's burger.

"Quite honestly, the positioning of the product was just not the right positioning," admitted Wendy's CEO Emil J. Brolick, a veteran QSR executive who comes from Yum Brands. "I personally have consistently seen that those $0.99 shoppers are generally $0.99 shoppers, and you're not likely to be able to move them up to that $2.99 price point," stated the CEO at the earnings call.

With over 12,500 locations, Burger King saw same store sales worldwide in its first quarter grow by 4.6 percent compared to 2011. U.S. same store sales increased 4.2 percent. In an earnings call to investors this morning, Daniel Schwartz, chief financial officer, said that this rise in comparable sales was largely from a chicken sandwich, new fries and a coupon offer. He declared: "We are particularly pleased with our performance in North America, which delivered its best comparable sales performance in more than eight quarters."

The burger chain franchisor wouldn't say what its April same store sales were. At the very end of March, the brand introduced to U.S. consumers the largest number of menu items it has ever launched — thirteen. Of the impact on the new menu items to its top line for April, Burger King Worldwide's CFO would only say, "We are very happy to see the sales results from the beginning of the second quarter."

Carrols Corporation, the largest of Burger King's franchise owners, provides a glimpse of how significant those sales figures are. The franchisee now has 278 restaurants. Its comparable sales for April were up by a whopping 9.5 percent for its stores.

"Carrols is a good proxy for Burger King franchise owners and the restaurants in the network," observes San Diego-based John Gordon, a restaurant economics analyst and founder of Pacific Management Consulting Group. The April jump in its sales is an indication what the chain's franchisees as a whole are experiencing.

"It looks like Burger King has managed to pull U.S. sales and traffic away from McDonald's and Wendy's," notes Gordon. "But we don't know how long that trend will last," Gordon is quick to add. The analyst thinks that Burger King will likely receive an additional four and a half percent bump to its sales growth for April from the introduction of its new menu items. He speculates that this trend could continue on in May as consumers are still curious to try the new items.

Burger King's CFO was shy to comment on the impact of the new menu items to traffic and sales, but did state in the earnings call: "It's still early days but we continue to see strong results."

Darren Tristano, executive vice president of foodservice research firm Technomic, agrees that the hit on McDonald's is temporary. "McDonalds still looks better than its peers," he states. He thinks this is likely a bump in the road created by an aggressive shift in Burger King’s strategy to its new fresh menu. This has resulted in shift in the market away from McDonald's toward Burger King. "Long term, I think McDonalds will continue to grow this year and see more consistent monthly same store sales performance," he declares.*

Worldwide

MCD data by YCharts

Worldwide sales for the month increased 2.2% for McDonald's.

Asia/Pacific, Middle East and Africa (APMEA) reported a comparable sales increase of 1.1% for April due largely from a contraction in Japan's giant market.

While Europe's austerity moves to shrink government spending has helped dampen the economies of the European Union and tightened the purse strings of its consumers; yet, McDonald's in Europe posted a 3.5% increase in comparable store sales for April within each of the segment's major markets – France, the U.K., Germany and Russia – contributing. Customer enthusiasm for the latest addition of the Monopoly game in Germany and the U.K., premium food events in France and Russia, as well as the ongoing benefits of restaurant reimaging, all fueled results for the month. That's in contrast to McDonald's reported systemwide sales in Europe, which were down 1.9 percent for April.

"Our focus on delivering great tasting food and an exceptional restaurant experience generated positive global comparable sales results in April," said McDonald's chief executive officer Jim Skinner and vice chairman of the board.  "Amidst a challenging global economic environment, McDonald's ongoing commitment to optimizing the menu, modernizing the restaurant experience and broadening accessibility will enable us to continue to satisfy the evolving needs of our customers."

Analyst John Gordon thinks there is still some of McDonald's sales and traffic to be eaten in the short-term by Burger King.

*Editor's note: Darren Tristano's quote was submitted shortly after the story was published online. His insights were added later.