Passively managed strategies continue to outpace active strategies domestically, but for international investments it's a different story.

BlackRock and Vanguard still rule institutional AUM, while four more managers joined the trillion-dollar club.

A heady brew of returns and fundraising success boosted alts managers' assets, but only three sectors saw double-digit growth in 2017.

Vanguard could surpass BlackRock by 2022 should compound growth rates of the past eight years continue.