Transportation Spending by Low-Income California Households ...

5. Commute Behavior in the Bay
Area
This chapter investigates how commute patterns—mode choice,
commute schedules, commute duration, etc.—vary across income groups
in the San Francisco Bay Area. As the analyses in the previous chapters
have demonstrated, mode choice can have a large effect on transportation
expenditures. However, more expensive modes may provide shorter
commute times or greater mobility. This chapter explores these tradeoffs.
In contrast to the CES data used in Chapter 3, the Census data used
here have information only about work-related trips, but on the other
hand, they do allow us to look specifically at the Bay Area. In spite of
the differences in the data sources used in the chapters, the investigation
of commute behaviors in this chapter helps illuminate some of the
reasons behind the differences in expenditures levels across groups.
Differences in Travel Patterns Across Income Groups
Mode choice for commutes differs tremendously by income level. 1
Seventy percent of higher-income Bay Area workers commute by driving
alone, whereas only 53 percent of the low-income group and 51 percent
of the poor group drive alone to work (Table 5.1). 2 Conversely, those in
the low-income category are twice as likely as those in the higher-income
group to take the bus or trolley bus (12% versus 5%), and more than
twice as likely to walk to work (7% versus 3%). The low-income group
also has slightly higher rates of carpooling and biking than the higherincome
group.
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1 Census respondents who commute using multiple modes were asked to report only
the mode by which they travel the longest distance.
2 The difference between the low-income and poor group is small but statistically
significant.
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