Population trends are a key factor affecting the volume of travel in the region. In addition, where and how people live greatly determines which transportation facilities and modes get used most and which warrant the greatest investment of transportation funding. For these reasons, the NJTPA maintains active programs to monitor and forecast demographic trends. NJTPA uses several sources of such data, including decennial census data (such as journey-to-work), intercensal surveys (such as the American Community Survey), and demographic forecasts.
Available data on NJTPA demographics have been divided into two sources: Forecasts and Census demographics.
The NJTPA Regional Transportation Plan adopted in 2005 describes regional demographics as follows:
The 13-county NJTPA region has seen strong growth in population in recent years. In 1990, there were nearly 5.8 million people in the region. By 2005, that number had grown to more than 6.5 million. In keeping with historic decentralization trends seen throughout the United States, the outlying areas experienced the most rapid growth in population and development in recent years, while cities and older suburbs in and around the urban core absorbed immigrants and other new residents to help stave off declining populations.
Regional growth will continue at a steady pace over the next 25 years, with population reaching more than 7.6 million in 2030, an increase of nearly 16 percent. Growth rates are expected to continue to be most rapid in the southern and western counties, including Ocean, Sussex and Warren. But it is significant to note that all counties in the region are expected to grow. In terms of absolute growth, Ocean County is expected to add more people than any other county, but dense, urban Hudson County and geographically diverse Middlesex County also will see large increases in terms of actual numbers. This widespread growth that cuts across rural, suburban and urban areas throughout the region presents an ongoing set of transportation challenges in terms of both the increasing volume of travel and how it is distributed throughout the region.