Illinois, the 21st state admitted to the United States of America, is the most populous and demographically diverse Midwestern state and the fifth most populous state in the nation. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and western Illinois, and natural resources like coal, timber, and petroleum in the south, Illinois has a broad economic base. Illinois is an important transportation hub; the Port of Chicago connects the Great Lakes to the Mississippi River via the Illinois River. Illinois is often viewed as a microcosm of the United States; an Associated Press analysis of 21 demographic factors found Illinois the "most average state", while Peoria has long been a proverbial social and cultural bellwether.