the sake of objectivity about the economy, but that argument was rejected. He stated: Later, the economist Robert Eisner tried to estimate the value of "non-market outputs". His calculations suggested that in the United States, the value of unpaid household work declined from about 45% of conventional Gross National Product in 1945 to about 33% in 1981. See also Comparative statics law of value labour power References Further reading Karl Marx, Das Kapital Andrew Trigg, Marxian Reproduction Schema. Routledge, 2006. Peter Custers, Questioning Globalized Militarism: Nuclear and Military Production and Critical Economic Theory. London: Merlin Press, 2008. Emilio Díaz Calleja, Teoría del capital: Una aproximación matemática al esquema de reproducción de Marx. Septiembre de 2010. Marxian economics Labour economics