Houston is the seat of Harris County and is the fourth-largest city in the country and the largest city of Texas. It is the home to the second highest number of Fortune 500 company's headquarters. The city's economy is based on, energy, manufacturing, aeronautics, transportation, and health care sectors. The average home value is $155,245; rent is $878 and the average income is $48,276. Allstate Insurance and State Farm Mutual Auto Insurance are the city's major financial service providers.