Spirit Airlines stock is rising on better-than-expected results. Image credit: The Motley Fool

Shares of Spirit Airlines (NYSE:SAVE) stock were up 4.2% as of 2:10 p.m. Eastern today, rising on better-than-expected fourth-quarter earnings. Here's a closer look at the final totals versus Wall Street's projections:

Spirit AirlinesRevenueYOY GrowthEPSYOY Growth
Consensus estimate  $475.71 million 7.6%  $0.78  39.3%
Fiscal Q2 actuals  $474.49 million 12.9%  $0.80  42.9%
DIFFERENCE  (1.22 million) 5.3%  $0.02  3.6%

Sources: S&P Capital IQ and Spirit Airlines press release

For the full year, Spirit Airlines reported $1,931.6 million in revenue and $3.23 a share in non-GAAP profit. Analysts tracked by S&P Capital IQ were calling for $1,932.9 million and $3.21 a share, respectively.

"During 2014, we improved our customers' understanding of our Bare Fare plus Frill Control product design, which led to increased customer satisfaction, improved our financial results, and maintained a very high completion rate while improving our on-time performance by 600 basis points," said CEO Ben Baldanza in a press release.

What went right: Spirit's fleet expansion included taking delivery of seven new A320 aircraft during the quarter, leading to an 18.9% increase in available seat miles (ASM) and a 17% increase in revenue passenger miles (RPM). The resulting efficiencies helped push cost per available seat mile (CASM) down 2.9% before accounting for fuel. 

What went wrong: Yet there's more work to do. Load factor dipped 1.4 percentage points as flights departed full just 84.8% of the time versus 86.2% in last year's Q4. Operating revenue per available seat mile also fell 5.1% as passenger ticket prices dipped 6.1%. Spirit remains in the early stages of putting its newest aircraft to work.

What's next: Unfortunately, Spirit Airlines didn't provide guidance in its press release. What can investors look forward to? Analysts tracked by S&P Capital IQ have the low-cost carrier generating $518.3 million in revenue and $0.99 a share in adjusted profits in the first quarter. Both figures would represent meaningful improvement over last year's Q1 results. ($437.99 million and $0.52, respectively). 

Longer term, they have Spirit Airlines generating 24.52% average annual earnings growth during the next three to five years.

Tim Beyers has plenty of Spirit but has never flown on Spirit Airlines. Nor does he own shares. Tim is also a member of the Motley Fool Rule Breakers stock-picking team and the Motley Fool Supernova Odyssey I mission. Check out his web home and portfolio holdings or connect with him on Google+Tumblr, or Twitter, where he goes by @milehighfool.

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