year,rel.beak.size,st.err
1972,0.303227758,0.440539515
1973,-0.034662154,0.158035398
1974,-0.052468783,0.204461287
1975,-0.295444512,0.107572848
1976,-0.22053349,0.063095555
1978,0.364163819,0.130241799
1979,0.401543023,0.123444891
1980,0.449959394,0.125478259
1981,0.379174365,0.110079026
1982,0.418761003,0.114339011
1983,0.372252291,0.081181155
1984,0.321328711,0.076791172
1985,0.285868066,0.092288854
1986,0.13781197,0.121298636
1987,0.031713459,0.068370816
1988,0.013895929,0.070541239
1989,0.009322999,0.083741158
1990,-0.021711878,0.097027512
1991,-0.066013157,0.083773273
1992,-0.088223752,0.092609718
1993,-0.081770416,0.090287522
1994,-0.066465545,0.099029225