{"Year":1961,"Yield":13026}
{"Year":1962,"Yield":14433}
{"Year":1963,"Yield":13142}
{"Year":1964,"Yield":16531}
{"Year":1965,"Yield":16469}
{"Year":1966,"Yield":17840}
{"Year":1967,"Yield":18419}
{"Year":1968,"Yield":14284}
{"Year":1969,"Yield":15986}
{"Year":1970,"Yield":19807}
{"Year":1971,"Yield":19926}
{"Year":1972,"Yield":19977}
{"Year":1973,"Yield":19905}
{"Year":1974,"Yield":23504}
{"Year":1975,"Yield":22919}
{"Year":1976,"Yield":25521}
{"Year":1977,"Yield":18813}
{"Year":1978,"Yield":27213}
{"Year":1979,"Yield":24301}
{"Year":1980,"Yield":29348}
{"Year":1981,"Yield":27556}
{"Year":1982,"Yield":28778}
{"Year":1983,"Yield":20925}
{"Year":1984,"Yield":26713}
{"Year":1985,"Yield":20464}
{"Year":1986,"Yield":26311}
{"Year":1987,"Yield":25971}
{"Year":1988,"Yield":28152}
{"Year":1989,"Yield":30163}
{"Year":1990,"Yield":19332}
{"Year":1991,"Yield":31183}
{"Year":1992,"Yield":24315}
{"Year":1993,"Yield":22961}
{"Year":1994,"Yield":27506}
{"Year":1995,"Yield":26341}
{"Year":1996,"Yield":24120}
{"Year":1997,"Yield":24170}
{"Year":1998,"Yield":24385}
{"Year":1999,"Yield":23914}
{"Year":2000,"Yield":27116}
{"Year":2001,"Yield":25089}
{"Year":2002,"Yield":23437}
{"Year":2003,"Yield":20085}
{"Year":2004,"Yield":24757}
{"Year":2005,"Yield":24223}
{"Year":2006,"Yield":22859}
{"Year":2007,"Yield":22353}
{"Year":2008,"Yield":29513}
{"Year":2009,"Yield":26218}
{"Year":2010,"Yield":31373}