Metro has released system-wide ridership data for January 2011 and there is some good news — ridership is up.

Compared to Jan. 2010, average weekday boardings increased from 1,324,006 to 1,385,083 in Jan. 2011 on all Metro transit lines combined (bus and rail). This represents a 4.6 percent increase over a year ago.

Here’s a quick breakdown of the year-over-year ridership numbers for average weekday boardings on various Metro lines. Go here for a link to all the raw data on Metro’s website and here for a PDF with useful graphs.

• Bus system-wide: Total increase of 36,652 riders — from 1,050,250 riders in Jan. 2010 to 1,086,902 riders in Jan. 2011 — representing an increase of 3.4 percent.
• Red and Purple Lines: Total increase of 4,225 riders — from 139,409 riders in Jan. 2010 to 143,634 riders in Jan. 2011 — representing an increase of 3.03 percent.
• Blue Line: Total increase of 9,126 riders — from 70,583 riders in Jan. 2010 to 79,709 riders in Jan. 2011 — representing an increase of 12.93 percent.
• Green Line: Total increase of 5,355 riders — from 35,536 riders in Jan. 2010 to 40,891 in Jan. 2011 — representing an increase of 15.07 percent.
• Gold Line: Total increase of 5,720 — from 28,227 riders in Jan. 2010 to 33,947 riders in Jan. 2011 — representing an increase of 20.26 percent (note that the Eastside Extension had already opened before Jan. 2010).

While this appears to be good news for Metro, it is important to remember that this is just one slice of data. It’s not a trend. Yet.

It’s also not immediately clear what is causing the increase: It could be the improving economy, higher and increasing gas prices in the Southland or more commuters wanting a way to avoid driving in traffic. In all likelihood, it’s some combination of all of these and more.

The overall increase from Jan. 2010 to Jan. 2011 represents only a partial recovery of the 100,000 average weekday riders that Metro lost from Jan. 2009 to Jan. 2010 as the American economy continued to falter.

As the Federal Bureau of Labor Statistics notes [PDF], for much of 2009 the U.S. was still losing hundreds of thousands of jobs each month. And when people don’t have a job to commute to, they certainly aren’t going to be taking the bus, train, rideshare — or drive — as often. This trend in 2009 was borne out nationwide. In the year, an American Public Transit Association (APTA) survey showed a national decline in transit ridership of 3.8 percent.

We’ll keep you updated more often on ridership numbers and hopefully will continue to have more good news tor report.