How was Wassily Leontief awarded the Noble Prize in Economics?

Name: Wassily Leontief.
Real Name: Wassily Wassilyevich Leontief.
Country: Russian, Soviet, American.
Date of Birth: 5 August 1905.
Died: 5 February 1999.
Education: University of Leningrad (MA), University of Berlin (PhD).
Subjects Of Study: Input-output analysis linear programming econometrics.
Known as: Input–output analysis.
Noble Prize Year: Nobel Prize for Peace in 1973, for the development of the input-output method and for its application to important economic problems.