https://www.pcgamer.com/this-is-a-rebound-year-for-ar-and-vr-headsets-idc-says/

Depending on your vantage point, it was a relatively weak year for AR and VR adoption in 2017. International Data Corporation (IDC) blames the overall "headset market retreat" on the decline in shipments of screenless VR viewers, which are headsets built for smartphones like the Gear VR. Despite constricting shipments, IDC is confident we are in for a rebound this year, followed by significant growth over the course of the next several years.

2018 will see a return to growth with combined AR/VR volumes reaching 12.4 million units, IDC says. That would mark an impressive year-over-year increase of 48.5 percent as new vendors and new use cases emerge. Looking further down the line, IDC anticipates that combined shipments will balloon to 68.9 million units in 2022, with a five-year annual compound growth rate of 52.5 percent.