Here are the historical canola yields for Alberta. Yes canola yields have increased over time, no point arguing that. However, expenses have also increased such that farm income really hasn't improved. The farm income historical tables are at
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/sdd10280/$FILE/table6.pdf
Table 86: Alberta Canola Yield, 1955-2004
Bushels per Acre
Source: Statistics Canada
Alberta Agriculture Statistics Yearbook, 2004
1955..................... 11.2
1956..................... 18.0
1957..................... 14.8
1958..................... 13.0
1959..................... 15.9
1960..................... 14.7
1961..................... 17.1
1962..................... 15.5
1963..................... 16.0
1964..................... 16.0
1965..................... 12.9
1966..................... 17.6
1967..................... 13.9
1968..................... 16.7
1969..................... 14.3
1970..................... 17.6
1971..................... 16.1
1972..................... 18.5
1973..................... 16.5
1974..................... 16.3
1975..................... 17.9
1976..................... 19.7
1977..................... 22.9
1978..................... 21.0
1979..................... 18.1
1980..................... 22.7
1981..................... 23.1
1982..................... 22.6
1983..................... 18.8
1984..................... 20.0
1985..................... 19.6
1986..................... 25.0
1987..................... 25.3
1988..................... 24.2
1989..................... 23.0
1990..................... 23.1
1991..................... 24.0
1992..................... 21.6
1993..................... 26.1
1994..................... 21.8
1995..................... 24.5
1996..................... 25.0
1997..................... 23.5
1998..................... 25.3
1999..................... 29.0
2000..................... 26.1
2001..................... 27.0
2002..................... 21.4
2003r.................... 29.7
2004p................... 33.9
2005e … … … … … .. 39.8
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/sdd10280/$FILE/table6.pdf
Table 86: Alberta Canola Yield, 1955-2004
Bushels per Acre
Source: Statistics Canada
Alberta Agriculture Statistics Yearbook, 2004
1955..................... 11.2
1956..................... 18.0
1957..................... 14.8
1958..................... 13.0
1959..................... 15.9
1960..................... 14.7
1961..................... 17.1
1962..................... 15.5
1963..................... 16.0
1964..................... 16.0
1965..................... 12.9
1966..................... 17.6
1967..................... 13.9
1968..................... 16.7
1969..................... 14.3
1970..................... 17.6
1971..................... 16.1
1972..................... 18.5
1973..................... 16.5
1974..................... 16.3
1975..................... 17.9
1976..................... 19.7
1977..................... 22.9
1978..................... 21.0
1979..................... 18.1
1980..................... 22.7
1981..................... 23.1
1982..................... 22.6
1983..................... 18.8
1984..................... 20.0
1985..................... 19.6
1986..................... 25.0
1987..................... 25.3
1988..................... 24.2
1989..................... 23.0
1990..................... 23.1
1991..................... 24.0
1992..................... 21.6
1993..................... 26.1
1994..................... 21.8
1995..................... 24.5
1996..................... 25.0
1997..................... 23.5
1998..................... 25.3
1999..................... 29.0
2000..................... 26.1
2001..................... 27.0
2002..................... 21.4
2003r.................... 29.7
2004p................... 33.9
2005e … … … … … .. 39.8
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