Flatter yield curve meant fx hedged purchases weren't as attractive for many private investors abroad.
And the tax reform mean US firms weren't holding funds abroad that they needed to invest in US assets.
But that's for another time
(6/x)
And if U.S. firms structurally hold less "cash" abroad, offshore demand for U.S. financial assets will also be a bit lower going forward
(10/x)
and of course in '18 have a one off stock adjustment too
(11/11)