Joint Venture Silicon Valley's annual economic study found that 2015 was a year of record-breaking growth and prosperity, but it cautioned that there are perils associated with this kind of break-neck trajectory: A fourth-quarter slowdown could portend the beginning of the burst of a bubble.

Joint Venture Silicon Valley's annual economic study found that 2015 was a year of record-breaking growth and prosperity, but it cautioned that there are perils associated with this kind of break-neck trajectory: A fourth-quarter slowdown could portend the beginning of the burst of a bubble.