► Subscribe to FT.com here: http://bit.ly/2r8RJzM
The US stock market's dependence on "Big Tech" to drive its gains has caused some concerns that a bubble is forming. But Robin Wigglesworth explains why it is too soon to call time on the rally.
► Subscribe to the Financial Times on YouTube: http://bit.ly/FTimeSubs
For more video content from the Financial Times, visit http://www.FT.com/video
Twitter https://twitter.com/ftvideo
Facebook https://www.facebook.com/financialtimes
