We construct revised near-infrared absolute magnitude calibrations for 126 Galactic Wolf-Rayet ( WR ) stars at known distances , based in part upon recent large scale spectroscopic surveys .
Application to 246 WR stars located in the field , permits us to map their Galactic distribution .
As anticipated , WR stars generally lie in the thin disk ( \sim 40 pc half width at half maximum ) between Galactocentric radii 3.5–10 kpc , in accordance with other star formation tracers .
We highlight 12 WR stars located at vertical distances of \geq 300 pc from the midplane .
Analysis of the radial variation in WR subtypes exposes a ubiquitously higher N _ { WC } / N _ { WN } ratio than predicted by stellar evolutionary models accounting for stellar rotation .
Models for non-rotating stars or accounting for close binary evolution are more consistent with observations .
We consolidate information acquired about the known WR content of the Milky Way to build a simple model of the complete population .
We derive observable quantities over a range of wavelengths , allowing us to estimate a total number of 1200 ^ { +300 } _ { -100 } Galactic WR stars , implying an average duration of { \sim } 0.25 Myr for the WR phase at the current Milky Way star formation rate .
Of relevance to future spectroscopic surveys , we use this model WR population to predict follow-up spectroscopy to K _ { S } { \simeq } 13 mag will be necessary to identify 95 % of Galactic WR stars .
We anticipate that ESA ’ s Gaia mission will make few additional WR star discoveries via low-resolution spectroscopy , though will significantly refine existing distance determinations .
Appendix A provides a complete inventory of 322 Galactic WR stars discovered since the VIIth catalogue ( 313 including Annex ) , including a revised nomenclature scheme .