Optical photometric lightcurve (left, red) and EW_Hα (right, blue) of LS I +61 303 folded with the orbital phase for the first (top) and second (center) seasons, and their sinusoidal fits to the orbital variability (bottom; see Table 3). Error bars represent 1σ uncertainties. Two cycles are displayed for clarity. The shifts in the orbital modulations between both seasons are clear.