R Leo H₂O-maser light curve in 1995-2011. We display the flux densities obtained from the line fit features seen between -2 and +2 km s⁻¹ (see text) vs. TJD. Data points marked by an asterisk are from Effelsberg and plusses are from Medicina data. Upper limits are shown as downward arrows in red. Times of maximum optical brightness defined by the sine wave fit to the optical data are indicated by dotted lines. Observations during the burst in 1997-1999 (TJD - 11 000) are connected by solid lines.