Panera Bread (PNRA) just posted its fourth-quarter results, which showed some improvement in both profit and sales. But as usual, there was much more to the earnings report than just the headline numbers.

In the video below, Fool contributor Demitrios Kalogeropoulos digs in to the restaurant chain's latest announcement, highlighting three factors that investors may have missed. First, he notes that Panera's comparable-store sales figure was a slight improvement over the prior quarter -- but a big drop from a year ago. That suggests the company still has plenty of work to do in getting its locations back to their industry-thumping growth levels.

Next, Demitrios points out that profitability shrunk in the quarter as Panera made necessary investments in labor and in the kitchens of its cafes. Many of those kitchens were overwhelmed during peak hours last year after Panera's aggressive menu expansion, and spending on boosting their throughput should pay off well.

Finally, Panera plans to significantly raise ad spending as a percentage of sales. That should help boost traffic levels while quickly putting those kitchen improvements to the test.