The research revealed that when individuals relied on cars for more than 50% of their out-of-home activities during a typical week, their satisfaction with life declined.
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*Answer: One way we measured car dependence was by asking respondents to estimate the percentage of time they rely on a car for out-of-home activities in a typical week. What we found is that, generally, as car dependence increases, life satisfaction tends to go up — but only to a certain point. Beyond that, we start to see a decrease.
To make sure the relationship we observed was not influenced by other factors, we used regression analysis and controlled for various external factors that other research has linked to life satisfaction. The tipping point, or threshold, where life satisfaction begins to decrease, is around 50%. When people rely on their car for more than half of their out-of-home activities, it seems to have a negative effect on their life satisfaction.*
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However, what we observed is that car dependence does not just affect how people feel while traveling — it seems to have a more lasting impact on overall life satisfaction. This finding is surprising because existing studies often display a weak link between car use and broader life satisfaction. Our research suggests that the effects of car dependence go beyond the immediate experience of a trip and may influence long-term sense of well-being.