Colorado. Population Population of Front Range area stretching from Colorado Springs to Boulder increasing by more than 100,000 every two years. RMN S 28, 1973 p.5 Colorado's 10.4% growth rate for 1970-73 ranks it 4th in the nation. RMN Jy 23, 1974 p.5 Birth rate at new low in Colorado. Post Ag 18, 1974 p.49 Map indicating population growth or decline in Colorado counties, 1960-70. Clips Growth falls from 3.9% average annual. growth rate to 1.1%, population figures also given. Post 0 23, 1974 p.1 RMN Q23, 1974 p>27