Googling for some data yields some results, but those seem to be big immigration numbers, rather than incidental short detentions for random travelers, so it's hard for me to draw any conclusion. Examples: http://cmsny.org/immigration-detention-behind-the-record-num... https://www.ice.gov/removal-statistics/2016
I think it's best to not get carried away just because a few people got detained. It seems a bit too little to call it policy shift for border control officers, at least as long it stays just incidental issue. FUD is always quick to spread and hard to fight against.