Question: What size population does the County Connection public transit in Concord, California service?
Context: Unitrans is the transit system which operates in Davis, California.  It takes its name from an abbreviation of the words "University Transport".  Excepting several managerial and maintenance positions, Unitrans is managed and operated entirely by students of the University of California, Davis who usually work part-time while attending school.  The system is well known throughout the area for its use of several distinctive ex-Transport for London double-decker buses, as well as its fleet of modern natural gas single-decks.  Ridership exceeds 3 million passenger-trips per year on 18 weekday, 2 school-only and 6 weekend routes.  Current fares are $1.00 for the general public and included in student fees for undergraduate University attendees.  Unitrans is one of a small number of transit systems in the United States to operate double deck buses in regular (non-sightseeing) service (the others include The Deuce in Las Vegas, Nevada, Antelope Valley Transit Authority in Lancaster/Palmdale, California, SLO Transit in San Luis Obispo and Community Transit in Snohomish County, Washington).  Unitrans has one of the best safety records of any public transit system in the US. The San Diego Metropolitan Transit System (MTS) (or sometimes abbreviated SDMTS or Metro) is the public transit service provider for Central, South, Northeast and Southeast San Diego County, in the United States.  MTS operating subsidiaries include the San Diego Trolley, Incorporated (SDTI), and San Diego Transit Corporation (SDTC).  Average daily ridership among all public transit services provided by MTS was 251,200 in the First Quarter of 2013. Saint John Transit is the public transit agency serving Saint John, New Brunswick, Canada.  Established in 1979 to provide scheduled transit service to the city, it is the largest public transit system in the province in terms of both mileage and passengers.  Ridership on Saint John Transit’s system is about 2.5 million passengers per year and growing. Martinez is an Amtrak passenger train station in Martinez, California, United States, the county seat of Contra Costa County.  The station was opened in September 2001, superseding a much earlier building that still stands a couple of blocks to the east.  Prior to the creation of Amtrak on May 1, 1971, passenger service was provided by Southern Pacific Railroad.  The station is served by local County Connection bus service and connecting service from WestCAT, and Tri-Delta Transit, as well as an Amtrak Thruway Bus Service.  The station includes a transit center for buses, passenger drop off and pick-up zones, a taxi stand, and surface level car parking, reserved for use by train passengers only. The County Connection (officially, the Central Contra Costa Transit Authority, CCCTA) is a Concord-based public transit agency operating fixed-route bus and ADA paratransit (County Connection LINK) service in and around central Contra Costa County in the San Francisco Bay Area.  Established in 1980 as a joint powers authority, CCCTA assumed control of public bus service within central Contra Costa first begun by Oakland-based AC Transit as it expanded into suburban Contra Costa County in the mid-1970s (especially after the opening of BART). Estuary Transit District, doing business as 9 Town Transit, is the public transit provider for Connecticut River Estuary region.  ETD provides public transit bus service through its 9 Town Transit service to the towns of Chester, Clinton, Deep River, Durham, Essex, East Haddam, Haddam, Killingworth, Lyme, Old Lyme, Old Saybrook, and Westbrook, Connecticut.  Services are provided to the general public, with no age or disability restrictions.  ETD was named the Rural System of the Year in 2011 by the Community Transportation Association of America. The Portland Transit Mall is a set of public transit corridors through the center of downtown Portland, Oregon, United States.  More specifically, it is a pair of one-way streets—one for northbound traffic, the other for southbound—along which two of the three lanes are restricted to transit vehicles only.  The transit mall opened in 1977 and until 2009, buses were the only transit vehicles using it, but in 2009 light rail was added.  Between 2007 and 2009 the mall was rebuilt and extended southwards, and it reopened for buses on May 24, 2009.  Light rail service on the mall was introduced on August 30, 2009, with the shifting of the MAX Yellow Line to the mall from its original routing in downtown, and a second MAX line, the Green Line, began serving the mall on September 12, 2009.  From fall 2009 to July 2014, the Portland Vintage Trolley also served the transit mall on certain Sundays.  Although the mall's transit stops are mainly served by TriMet vehicles, on weekdays buses on express routes operated by C-Tran and the Columbia County Rider also serve the mall.  In September 2015, the new MAX Orange Line replaced the Yellow Line service in the southbound direction on the mall, on 5th Avenue, with the Orange and Yellow lines being through-routed at all times. Trams (有轨电车) and Trolleybuses (无轨电车) in Beijing comprise part of the city's public transit infrastructure.  The earliest tram service in Beijing dates back to 1899, and trams were the main form of public transit from 1924 to the late 1950s before they were replaced by trolleybuses that follow the tram routes they replaced.  In 2008, tram service returned to Beijing with the introduction of a tourist tram on Qianmen Avenue.  A number of tram and light rail lines started construction in Beijing.  The first one true public transit tram line that will open is the Western Suburban Line, which is scheduled start operating in 2017.  A tram line is expected to start construction in Yizhuang by the end of 2017.  A second tram line is under construction in Shunyi. Concord ( ) is the largest city in Contra Costa County, California.  At the 2010 census, the city had a population of 122,067 making it the 8th largest city in the San Francisco Bay Area.  Founded in 1869 as the community of Todos Santos by Salvio Pacheco, the name was changed to Concord within months.  The city is a major regional suburban East Bay center within the San Francisco Bay Area, and is 29 mi east of San Francisco. Tri Delta Transit, formally the Eastern Contra Costa Transit Authority, is a joint powers agency of the governments of Pittsburg, Antioch, Oakley, Brentwood, and Contra Costa County that provides bus service for the eastern area of Contra Costa County, California, United States.  Tri Delta Transit local buses connect to the BART rapid transit system at Pittsburg/Bay Point and Concord.  Tri Delta Transit buses also connect with County Connection bus service, WestCAT bus service, Delta Breeze bus service and Amtrak at shared bus stops.
Answer: a population of 122,067