What happened

Shares of gas card provider FleetCor Technologies (CPAY -2.24%) jumped as much as 11.9% in early Thursday trading, before settling down to a more modest 9.9% gain as of 11:45 a.m. EST.

So what

On Wednesday night, FleetCor reported estimate-topping earnings of $1 per share for its fiscal fourth quarter -- a 79% increase year over year -- and earnings of $4.75 for the year on $1.83 billion in sales. Those full-year profits climbed a healthy 23% year over year. Not bad for a company that grew its sales only 8%.

Woman using fuel payment card at pump.

FleetCor stock is gassing up and racing ahead. Image source: Getty Images.

Now what

FleetCor also issued new guidance along with its earnings news. Q1 2017 earnings are expected to range between $1.82 and $1.88 per share -- pro forma. Longer term, FleetCor is guiding investors to expect full-year profits of anywhere from $8.10 to $8.30 per share (again pro forma), on sales of between $2.17 billion and $2.23 billion.

Granted, from the more important GAAP perspective, FleetCor is only projecting profits of somewhere between $5.78 and $5.98 per share. That works out to a rather optimistic valuation of 28.3 times earnings on the stock, based on where the shares are trading after FleetCor's post-earnings run-up. Still given that the stock has grown earnings at a healthy 27% annual clip over the past five years, even 28 times earnings may not be too much to pay for FleetCor.