Who won the college football national championship in 1910-1919?

Record is shown as w-l-t

1910 Harvard 8 0 1
1911 Princeton 8 0 2
1912 Harvard 9 0 0
1913 Harvard 9 0 0
1914 Army 9 0 0
1915 Cornell 9 0 0
1916 Pittsburgh 8 0 0
1917 Georgia Tech 9 0 0
1918 Pittsburgh 4 1 0
1919 Harvard 9 0 1