Metro's iconic rail map, in distribution since Lance Wyman and Bill Cannan (Wyman & Cannan) designed it in 1976, takes – according to some observers – a "pop art" approach to representing its subway network. The Metro rail map uses thick strokes to mark its radial lines. To fit in the current space and make use of the iconography as currently proportioned, the map relies upon the fact that no more than two lines overlap at any single location. The addition of the Silver Line creates a three-line overlap from Rosslyn to Stadium–Armory, a fact that led WMATA to publicly announce in 2010 that it was considering a new map design. A number of unofficial attempts by graphic designers to redraw the Washington Metro map to include the Silver Line have done so by thinning the strokes throughout.