Abundance ratios as a function of age for our subsample of 120 dwarf stars of the thin disk population. Stars with planets are indicated by black symbols. For sodium, the abundance ratios from both equivalent widths and spectral synthesis determination are plotted. The vertical dashed line indicates the adopted solar age (4.53 Gyr). The 95% confidence intervals (solid lines) around linear regressions and their respective correlation coefficients (r) are also shown. The linear regressions were derived either for age ≤4.53 Gyr, age ≥4.53 Gyr, or for the whole range in age, depending on which one has the more significant slope.