U.S. airlines had a monster 2015 — not that it helped you much.

Look no further for proof that the U.S. airline industry is raking it in.

The U.S. Department of Transportation reported Monday that passenger airlines in the U.S. had an after-tax net profit of $25.6 billion in 2015 — compared to a mere $7.5 billion in 2014.

Before taxes, the 25 airlines with scheduled passenger service reported a $28 billion operating profit in 2015, up from $14.6 billion in 2014, according to the Bureau of Transportation Statistics.

The spike in profits is even more stark when compared to overall sales for airlines, which actually dipped slightly. The airlines' total operating revenue last year was slightly down, to $168.9 billion, from $169.3 billion in 2014.

That revenue decline is almost irrelevant thanks to lower fuel costs, which in 2014 totaled $43.4 billion, but in 2015 went down to $27 billion.

Consumers also saw some benefit from airlines’ banner year. Average airfares were also down 3.8% in 2015, to $377 — the lowest since 2010. Travelers may or may not have felt the benefits of lower average airfares, as they have been accompanied by the rise of extra fees in recent years.

Labor costs increased year over year for the airlines from $40.8 billion to $45.4 billion.

About 75% of 2015's operating revenue — $126.9 billion — came from fares.

Of course, airlines also make money from extra fees, and revenue from baggage fees increased to $3.8 billion, from $3.5 billion in 2014. Revenue from reservation change fees stayed flat at about $3 billion.

There are other fees airlines make money from, like seating assignments and in-flight sales, but the Transportation Department does not have separate data tracking those numbers.