Source: http://blogs.wsj.com/digits/2015/09/18/s...

Wondering if the Silicon Valley’s tech boom is waning? Look no further than Caltrain, which shuttles workers between home and the region’s tech giants including Google Inc.GOOGL -2.01%, Twitter Inc.TWTR -2.01% and Salesforce.com Inc.CRM -0.68%

The number of passengers on the commuter train line reached a record high of more than 58,000 riders on an average weekday in the 12 months through June, the transit agency announced recently, more than 20,000 more than four years ago. Since 2011, Caltrain has experienced annual ridership growth of at least 10%.

The boom in tech jobs in the region means more and more tech workers need to get to work – and then home again – creating a transit crisis in the region. It makes sense that so many workers take the Caltrain to their jobs, because the train, which runs 77 miles from San Francisco in the north to Gilroy in south, is the fastest way to get from Silicon Valley to San Francisco during rush hour, without the help of a helicopter. Just three stations—San Francisco, Palo Alto and Mountain View—handle an outsize portion of the train’s riders: about half of all passengers get off at one of those three stops.