Were Keys Left Inside Nearly Half of Vehicles Stolen in Texas?

In urging people to take their keys with them when they leave their cars, Williamson County Sheriff Robert Chody claimed in a post on Twitter, "Almost half of all vehicles stolen in Texas each year had keys left inside." Is that true? We asked Gardner Selby of PolitiFact Texas. You can read the fact-check here: http://www.politifact.com/texas/statements/2018/jan/12/robert-chody/nearly-half-texas-vehicle-thefts-keys-left-inside-/