Kroger (NYSE:KR) this morning posted first-quarter earnings results that included market-thumping sales gains. Earnings spiked higher by 14% as the grocery store chain outgrew all other major national food retailers. Up 54% in the past year, the stock rose by a further 3% immediately following the announcement.

Source: Kroger

Here's a big-picture look at how the headline results stacked up against Wall Street's expectations.

Metric Expected Actual
Revenue $33.3 billion $33.1 billion
Profit $1.22 per share $1.25 per share

"Expected" is the average target of the 20 analysts that cover the stock. Source: Yahoo! Finance and Kroger financial filing

Soaking up market share
Sales growth was held to just 0.3% thanks to sinking fuel prices that pinched Kroger's bustling gasoline business. More importantly, comparable-store sales, which strips out volatile fuel price swings, spiked higher by 5.7%. 

For investors keeping score, that marks the fifth consecutive quarter in which Kroger has grown faster than Whole Foods(NASDAQ:WFM). The grocer also trounced Wal-Mart's 1.1% first-quarter comps -- and even passed Costco's 5% growth. Kroger is clearly doing a few things right to be outpacing all of its food retailing rivals. Management thinks its customer satisfaction focus has been the key difference. "Our results show the power of our customer first strategy," CEO Rodney McMullen said in a press release.

Surprisingly high profits
Profits came in ahead of Wall Street estimates, climbing to $612 million, or $1.25 per share, from $557 million, or $1.09 per share, a year ago. The grocer trimmed costs from its operations, which helped lift profit margin ahead of expectations. Operating profit jumped to 3.3% of sales from 2.8% last year.

That's important because Kroger's formidable earnings position gives it leverage to keep intense pricing pressure against its grocery rivals. Management said they spent $3.5 billion on price cuts last year, and rising profitability means that Kroger can afford to be even more ruthless on pricing in 2015. 

Boosted outlook
Executives affirmed their full-year earnings forecast that calls for profits of $3.85 per share. However, sales growth is outpacing their prior expectations: Management raised Kroger's 2015 comps outlook from 3.5% to 4%. 

That forecast implies Kroger could reach 50 straight quarters of positive comps within the next year. Still, the executive team seems to understand that it will take plenty of hard work to get to that point.

"Kroger has produced consistently remarkable results for so long that it might be easy for some to take a quarter like this for granted -- so it is important to emphasize it is the efforts of our incredible team of associates, connecting with customers, that is driving our success," McMullen said. "Time and again, we have shown that by taking care of our customers, Kroger is creating sustainable value for our shareholders," he added.