As of 2006, Indiana had an estimated population of 6,313,520, which is an increase of 47,501, or 0.8%, from the prior year and an increase of 233,003, or 3.8%, since the year 2000. This includes a natural increase since the last census of 196,728 people (that is 541,506 births minus 344,778 deaths) and an increase due to net migration of 51,117 people into the state. Immigration from outside the United States resulted in a net increase of 68,935 people, and migration within the country produced a net loss of 17,818 people.
The center of population of Indiana is located in Hamilton County, in the town of Sheridan. Population growth since 1990 has been concentrated in the counties surrounding Indianapolis, with four of the top five fastest-growing counties in that area: Hamilton, Hendricks, Johnson, and Hancock. The other county is Dearborn County, which is near Cincinnati.
The Evansville area has experienced a shift in their population. Vanderburgh County has continued to grow by at least 3% a year while the city of Evansville struggles with retaining population. The other counties of the Evansville area of Southwestern Indiana have started to grow at an increasingly faster rate, especially Gibson and Warrick Counties who are becoming Evansville's suburban counties. Gibson County has seen at least two towns Haubstadt and Fort Branch starting to become "bedroom communities" like Newburgh and Chandler in Warrick County. In addition, the two counties have seen their minority (in particular, Asian, African-American, and Hispanic) populations nearly double in the last 15 years.
As of 2005, the total population included 242,281 foreign-born (3.9%).
German is the largest ancestry reported in Indiana, with 22.7% of the population reporting that ancestry in the Census. Persons citing "American" (12.0%) and English ancestry (8.9%) are also numerous, as are Irish (10.8%) and Polish (3.0%).
Although the largest single religious denomination in the state is Roman Catholic (836,009 members), most of the population are members of various Protestant denominations. The largest Protestant denomination by number of adherents in 2000 was the United Methodist Church with 288,308. A study by the Graduate Center found that 20% are Roman Catholic, 14% belong to different Baptist churches, 10% are other Christians, 9% are Methodist, and 6% are Lutheran. The study also found that 16% are secular.
The state is home to the University of Notre Dame and several other private, religiously affiliated schools. It also has a strong parochial school system in the larger metropolitan areas. Southern Indiana is the home to a number of Catholic monasteries and one of the two archabbeys in the United States, St. Meinrad Archabbey. Two conservative denominations, the Free Methodist Church and the Wesleyan Church, have their headquarters in Indianapolis as does the Christian Church (Disciples of Christ). The Fellowship of Grace Brethren Churches maintains offices and publishing work in Winona Lake. Huntington serves as the home to the Church of the United Brethren in Christ. Anderson is home to the headquarters of the Church of God (Anderson) Ministries and Warner Press Publishing House. Fort Wayne is the headquarters of the Missionary Church. Fort Wayne is also home to one of The Lutheran Church Missouri Synod's seminaries - Concordia Theological Seminary. The Friends United Meeting of the Religious Society of Friends, the largest branch of American Quakerism, is based in Richmond. Richmond also houses the oldest Quaker seminary in the US, the Earlham School of Religion. Indiana is home to an estimated 250,000 Muslims. The Islamic Society of North America is headquartered just off Interstate 70 in Plainfield, west of Indianapolis.
In 1906, the Census reported there were 938,405 members of different religious denominations; of this total, 233,443 were Methodists (210,593 of the Northern Church); 174,849 were Roman Catholics, 108,188 were Disciples of Christ; 92,705 were Baptists (60,203 of the Northern Convention, 13,526 of the National (African American) Convention; 8,132 Primitive Baptists, and 6,671 General Baptists); 58,633 were Presbyterians (49,041 of the Northern Church, and 6,376 of the Cumberland Church—since united with the Northern); 55,768 were Lutherans (34,028 of the Evangelical Lutheran Synodical Conference, 8,310 of the Evangelical Lutheran Synod of Ohio and other states), 52,700 were United Brethren (48,059 of the Church of the United Brethren in Christ; the others of the " Old Constitution "), 21,624 of the German Evangelical Synod; and 10,219 members of the Churches of Christ.
Indianapolis International Airport serves the greater Indianapolis area and has just finished constructing a new passenger terminal. The new airport opened in November 2008 and offers a new midfield passenger terminal, concourses, air traffic control tower, parking garage, and airfield and apron improvements.
Other major airports include Evansville Regional Airport, Fort Wayne International Airport (which houses the 122d Fighter Wing of the Air National Guard), and South Bend Regional Airport. A long-standing proposal to turn the under-utilized Gary Chicago International Airport into Chicago's third major airport received a boost in early 2006 with the approval of $48 million in federal funding over the next ten years.
The Terre Haute International Airport has no airlines operating out of the facility but is used for private flying. Since 1954, the 181st Fighter Wing of the Indiana Air National Guard has been stationed at the airport. However, the BRAC Proposal of 2005 stated that the 181st would lose its fighter mission and F-16 aircraft, leaving the Terre Haute facility as a general-aviation only facility.
The southern part of the state is also served by the Louisville International Airport across the Ohio River in Louisville, Kentucky. The southeastern part of the state is served by the Cincinnati/Northern Kentucky International Airport also across the Ohio River in Florence Kentucky. Many residents of northwestern Indiana use the two Chicago airports, O'Hare International Airport and Chicago Midway International Airport.
The major U.S. Interstate highways in Indiana are I-465, I-469, I-69, I-65, I-94, I-70, I-74, I-64, I-80, and I-90. The various highways intersecting in and around Indianapolis, along with its historical status as a major railroad hub, and the canals that once crossed Indiana, are the source of the state's motto, the "Cross-roads of America."
There are also many state highways maintained by the Indiana Department of Transportation. These are numbered according to the same convention as U.S. Highways.
Most Indiana counties use a grid-based system to identify county roads; this system replaced the older arbitrary system of road numbers and names, and (among other things) makes it much easier to identify the sources of calls placed to the 9-1-1 system. Such systems are easier to implement in the glacially flattened northern and central portions of the state. Rural counties in the southern third of the state are less likely to have grids and more likely to rely on unsystematic road names (e.g., Harrison County); there are also counties in the northern portions of the state that have never implemented a grid, or have only partially implemented one. Some counties are also laid out in an almost diamond-like grid system (e.g. Clark, Floyd and Knox Counties). Such a system is also almost useless in those situations as well. Knox County once operated two different grid systems for county roads because the county was laid out using two different survey grids, but has since decided to use road names and combine roads instead.
A notable county road system within the state is St. Joseph County's county road grid, which is relatively easy to follow. St. Joseph County, whose major city is South Bend, uses perennial (tree) names (i.e. Ash, Hickory, Ironwood, etc.) in alphabetical order for North-South roads and Presidential and other noteworthy names (i.e. Adams, Edison, Lincoln Way, etc.) in alphabetical order for East-West roads. There are exceptions to this rule in downtown South Bend and Mishawaka.
Indiana has over 4,255 railroad route miles, of which 91 percent are operated by Class I railroads, principally CSX Transportation and the Norfolk Southern Railway. Other Class I railroads in Indiana include the Canadian National Railway and Soo Line Railroad, a Canadian Pacific Railway subsidiary, as well as Amtrak. The remaining miles are operated by 37 regional, local, and switching & terminal railroads. The South Shore Line is one of the country's most notable commuter rail systems extending from Chicago to South Bend. Indiana is currently implementing an extensive rail plan that was prepared in 2002 by the Parsons Corporation.
Indiana annually ships over 70 million tons of cargo by water each year, which ranks 14th among all U.S. states. More than half of Indiana's border is water, which includes 400 miles (640 km) of direct access to two major freight transportation arteries: the Great Lakes/St. Lawrence Seaway (via Lake Michigan) and the Inland Waterway System (via the Ohio River). The Ports of Indiana manages three major ports which include Burns Harbor, Jeffersonville, and Mount Vernon.