Notice all that traffic on Colorado backroads? "More people are deciding to live full-time in Colorado's resort communities," according to the AP. Some are retirees who have decided to live year-round in vacation homes, while others have been drawn by the construction boom. Primary residences, as opposed to second homes, grew from 53 percent of the market in 1990 to 62 percent in 2000. Those figures cover Colorado's eight mountain resort counties. The shift is helping make the Western Slope the fastest growing part of the state. The full-time combined population of Eagle, Grand, Garfield, Summit, Pitkin and Routt counties is expected to more than double from 192,000 to 389,000 by 2030, according to the state demographer's office.