  Context: Methanol masers at 6.7GHz are recognised markers of high-mass star
formation regions. The study of their distribution in the Galaxy gives
important insights into the star formation activity of the Milky Way. We
present a statistical analysis on the General Catalogue of 6.7GHz methanol
masers in the Galaxy with the aim of extracting global properties of the
masers. Aims: We provide constraints on the luminosity function of 6.7GHz
methanol masers and on their total number in the Galaxy. Methods: We model the
spatial distribution of the masers in the Milky Way by using their distribution
in galactocentric distance which is unambiguous once a rotation curve for the
Galaxy is assumed. This is the starting point for determining the luminosity
function of the masers. Results: The luminosity function of 6.7GHz methanol
masers is modelled as a power-law with sharp cutoffs and having an index lying
between -1.5 and -2. We also predict the number of detections of methanol
masers assuming different sensitivity limits in the observations.
