pittsburgh;1900-2000

population of the city of

pittsburgh; 1900-200

production of steel by

USSteel Corportation;

1900-2000

USSteel detail

population of greater

metropolitan pittsburgh;

1900-2000

number of books in the

carnegie public library

system; 1900-2000

average number of rides on

public transportation per

resident; 1900-2000

percentage of immigrant

population in the city of

pittsburgh; 1900-2000

pittsburgh steelers win/loss

percentages; 1900-2000

pittsburgh; 1900-2000