As noted in Brief 12, the auto boom appears to have completed its rapid growth cycle and has stabilized at very high levels, remaining the dominant mode. However, in the past decade or so, there are modest signs of auto commuting retrenchment and evidence that other travel options are showing renewed use. This brief presents data describing bicycling and walking commuting trends and relationships. It should be noted that these modes, which hover around a three percent share for commuting, are more challenging to comprehensively analyze with statistically significant data due to their modest share and the constraints of sample size in both American Community Survey (ACS) and National Household Travel Survey (NHTS) data sources.