People per square mile in metropolitan Tucson in 1953: 5,000


in 1998: 2,400





Acres of Sonoran Desert land cleared for new homes, offices and commercial buildings each day: 12





Average annual temperature in Tucson in 1900: 67 degrees


in the mid-1990s: 70.5 degrees


(Pavement and buildings retain heat.)





Total annual vehicle miles traveled in the Tucson area in 1970: 2 million


in 1997: 16 million


expected in 2020: 28 million





Percentage of all Pima County vehicle trips lasting more than 30 minutes in 1968: 5


in 1998: 15





Speed of rush-hour crosstown trips on major Tucson thoroughfares: between 18 and 30 mph





Expected increase in the staff of the Pima County Sheriff's Department by the year 2020: 874 people


Expected number of new jail beds in Pima County: 4,000





Number of rabbits, mice, rats, birds and reptiles eaten by a typical Tucson housecat each year: 80





Number of toads, rabbits, snakes, lizards, small birds, javelinas, coyotes and bobcats killed each year by automobiles in and around Saguaro National Park: 7,100





Sources: Pima County Administrator's Office, City of Tucson, Pima Association of Governments, Arizona Department of Economic Security, Pima County Sheriff's Department, University of Arizona School of Renewable Natural Resources, National Weather Service, National Park Service and U.S. Forest Service.