Metro riders have been asked to pay more for Metro service four times in the past five years, yet their fares still do not cover the cost of running the trains, buses and MetroAccess vans around the region.

Even with some fares hitting $5.75 for a one-way trip with the SmarTrip discount, riders' fares only cover about half the overall costs to operate the entire system, according to Metro. But those ratios change depending on which mode of travel riders take.

Metrorail fares will cover about 71 percent of each trip in the current budget, according to Metro's projections. Metrobus fares will cover just 25 percent, while MetroAccess fares cover less than 7 percent.

Subway system's farebox recovery
The share of operating expenses for the largest U.S. subway systems that is covered by riders' fares.
New York City's MTA: 76.6%
San Francisco's BART: 76.1%
D.C.'s Metrorail: 67.7%
Chicago's CTA: 52.0%
Boston's MBTA: 51.3%
Atlanta's MARTA: 35.8%
Source: Federal Transit Administration, fiscal 2011 (latest data available)

The rest of the costs are mainly covered by taxpayer dollars.

To be sure, nearly all transportation systems in this country, from the airlines to the highway system, are subsidized in some way. Transit services like Metro help reduce other societal costs, such as the expense of building more roads to handle additional cars, costs of air pollution and traffic congestion delays.

Compared with other large subway systems, Metrorail ranks behind New York City's MTA and San Francisco's BART for having riders cover costs but ahead of Chicago, Boston and Atlanta, according to the Federal Transit Administration's latest figures, from fiscal year 2011.

And the situation is nothing new. "Since inception, the Authority has operated at a loss, which has been fully subsidized each year by the participating jurisdictions," according to an outside audit issued last month.

The estimated cost of a single rail trip on average this year will cost the agency $4.11 to deliver. Riders will pay on average 70.6 percent, or $2.90, of that cost, according to figures the agency recently shared with its board. A fifth of it, about 84 cents, is paid by taxpayers, and the remaining 9 percent comes from other revenue.

The agency raises money from other sources such as advertising and cellphone service providers. But they also have gotten money from real estate leases, such as new deal to get $75,000 per year for a Pentagon-area cellphone tower or from renting a Fairfax County home.

A bus trip is even more expensive for the transit agency to deliver. The average bus trip costs the agency $4.35 to deliver, according to Metro. On average, riders' fares cover just $1.09 of that, or 25 percent, once all the senior discounts and transfers are taken into account.

For MetroAccess, the service for riders' with disabilities, the share that riders pay is even smaller. The average trip costs Metro $52.02 per rider, with just about 6.7 percent, or $3.50, covered by riders. That cost per trip has soared in recent years, in part, because the system's ridership has decreased. But the system still has essentially the same costs to meet federal disability requirements.

Meanwhile, the capital budget that pays for repairs, maintenance and expansion of Metro's facilities and equipment is not paid for by riders' fares. Instead, taxpayers will cover the $5.3 billion price tag over five years, with about 50 percent paid for with federal funds and the rest coming from an assortment of state and local funds.