That seems to be very little for a railroad to earn....
Net income is what you might think of as "profit." Despite its status as a state-owned corporation, the railroad actually does turn a profit.
What you were thinking of as "earnings," i.e., operating revenue, is pretty respectable: in 2011, it was $161.5 million. That puts it well into the middle of the pack of the "class II" or "regional" railroads.
I am not familiar with ARR freight traffic. Didn't even know they mined coal in Alaska.....
ARR freight traffic consists of four major parts:
-Petroleum, which primarily consists of shipping fuel from the Flint Hills North Pole Refinery southeast of Fairbanks to Anchorage,
-General freight, which the ARR breaks out into TOFC and "interline," which are whole railcars barged up to Whittier on the Alaska Rail Marine or CN Aqua Train rail barges
-Gravel, which consist of usually three or more trains that bring crushed rock from quarries in the Mat-Su valley about 45 miles north of Anchorage into Anchorage itself, largely to be used in road construction, and
-Coal, which consists of two parts: "local coal," which brings coal a few times a week from the Usibelli coal mine near Healy north to Fairbanks, whose power is largely supplied by coal, and "export coal," which brings coal a few times a month from the Usibelli mine to the port at Seward to be shipped out of state (mostly to South Korea, leading to the other colloquial name for the coal run, "Korean coal").
The ARR typically runs two freights a day in each direction between ANC and FAI in the summer. They are referred to as the "OX" (the Oil Express) and the "FOX" (the Fairbanks Overnight Express). They typically depart each terminal in the evening (one around 6pm and the other around 8pm), taking just under 12 hours to reach the other terminal. The OX is made up of mostly tank cars, and the FOX is typically a mix of mostly freight (TOFC/COFC) with whatever leftover oil wouldn't fit on the OX. The tanks run full south and empty north, and the trailers and flatcars typically run full north and empty south. The wintertime often sees that slimmed down to one train per day, as freight traffic drops substantially (it's too cold to build anything) and the airport demand is lessened with fewer flights.
A large portion of the daily shipment (IIRC, about 2/3 of the tanks heading south each day) is Jet-A destined for the Anchorage airport, a major trans-Pacific cargo hub. It takes two tank cars to fill a single 747-400, and I counted 72 747s arriving at ANC in the last 24 hours out of about 220 flights; a good chunk of the rest were 777s, 767s, and MD-11 cargo planes, with the remainder being passenger flights (Alaska Airlines operated 34 flights into ANC in the last 24 hours and does close to double that in the summer) and some GA.
Note that the ARR is simply predicting a drop to basically $3 million in profit this year, not a drop to $3 million in revenue. They are still going to make a profit and will be around for a long time to come--the state is far too dependent on rail transport to see levels drop to where the railroad itself is in jeopardy of continued existence.