Table 6
Mobiles, Travellers & Travel Time Expenditures
San Francisco Bay Area: 1965, 1981 & 1990 Household Travel Surveys

Variable 1965 1981 1990 Percent Change
1965 - 1990
Household Population (age 5+) 3,920,000 4,727,400 5,330,400 36%
Mobile Population (age 5+) 3,124,500 3,871,700 4,378,900 40%
Mobile Population Share (%) 80% 82% 82%
"Travellers" (age 5+) 2,610,200 3,503,300 4,071,400 56%
"Traveller" Population Share (%) 67% 74% 76%
Total Households 1,386,800 1,970,400 2,246,300 62%
Mobile Households 1,302,700 1,786,000 2,072,500 59%
Mobile Household Share (%) 94% 91% 92%
"Travelling" Households 1,231,500 1,730,400 2,011,300 63%
"Travelling" Household Share (%) 89% 88% 90%
Total Trips, All Modes 12,172,400 17,168,100 16,966,700 39%
Person Hours of Travel, All Modes 3,763,500 5,569,300 6,021,200 60%
Average Trip Duration, All Modes 18.6 19.5 21.3 15%
Person Trips (Mechanized Modes) 9,737,200 14,527,400 14,811,400 52%
Person Hours of Travel, Person Trips 3,188,200 4,957,000 5,444,600 71%
Average Trip Duration, Person Trips 19.6 20.5 22.1 12%
Trip Rates (Average Weekday)
Total Trips per Mobile Pop. 3.90 4.43 3.87 -1%
Person Trips per "Traveller" 3.73 4.15 3.64 -2%
Total Trips per Mobile HH 9.34 9.61 8.19 -12%
Person Trips per "Travelling" HH 7.91 8.40 7.36 -7%
Total Trips per Total Household 8.78 8.71 7.55 -14%
Person Trips per Total Household 7.02 7.37 6.59 -6%
Travel Time Expenditures (Average Weekday, in Minutes)
Total Travel Time per Mobile Person 72.3 86.3 82.5 14%
Total Travel Time per "Traveller" 73.3 84.9 80.2 9%
Total Travel Time per Mobile HH 173.3 187.1 174.3 1%
Total Travel Time per "Travelling" HH 155.3 171.9 162.4 5%