There were strong relative flows to passive: In the US mutual fund (unit trust) and ETF savings pool, net flows in 2016 were $340bn out of active and $505bn into passive. Even more dramatic is the story for equity funds since 2008; investors have invested $1.3trn into passive equity funds and withdrawn $0.9trn from active equity funds. That’s a $2.2trn switch in investment style ove...