Rail transit’s association with gentrification has been a presence in the public discourse for some time and Los Angeles is no different. There is a prevailing public perception that Los Angeles' recent boom in rail transit development causes an influx of high income residents and an outflow of low income residents near rail stations. The authors' research asks whether the presence of rail transit increases the outflow lower-income neighborhood residents. The authors use a unique dataset of tax filers in Los Angeles County to address this question. This database tracks the income and location of households across 21 years at a fine spatial scale. This analysis aggregates household data to provide station-area population out mobility rates for 35 rail station neighborhoods and 35 paired control neighborhoods along two Los Angeles Metro transit lines. Their sample consists of 15 stations along the Red/Purple subway line and 20 station along the Gold light rail line that opened between 1993 and 2013. The authors measure effects on four income brackets: below 30% of Area Median Income (AMI) (<$15,000 in 2013), 30-50% of AMI, 50-80% of AMI and above 80% of AMI (>$40,000 in 2013).