Out of ~16,000 franchised dealerships I would say less than 10% because most have some sort of OEM program. In those cases the website provider probably has a GA account setup for them. The real question is "how many dealers know how many GA scripts are installed on their website?"
For example:
I did the original GA install on Checkered Flag (#1). We divorced the original, under my watch, when I got more educated on how to use it. Reinstalled (#2), but didn't get rid of the tag. Dealer.com installed their own (#3). I left and [USER=1245]@Christine Plunkett[/USER] took over the job. I know another version was installed on her watch (#4). When she left [USER=8408]@Ryan Montville[/USER] was promoted into the job and he now has his own GA version (#5) and I can only assume their current website provider, Dealer Inspire, has their version too (#6).
Other digital marketing vendors have asked for accesses and/or their own versions installed. I can't say how many different GA tags are on Checkered Flag's digital properties, because Dealer Inspire is the only one who can answer that. CDK would have to answer for the OEM programs that are on their platform and Dealer.com would have to do the same for the ones they host.
There is no way for Checkered Flag to know what is actually installed in their own website. I would bet there are at least 2 tags active per site.
You had to throw those two little words in there didn't you. I'm going to say this is less than 1%. I would give [USER=4695]@reverson[/USER] [USER=3505]@craigh[/USER] [USER=4107]@jon.berna[/USER] [USER=4779]@georgenenni[/USER] enough credit to do it right. But there isn't even a website company out there who I have enough confidence in to believe they got their own GA accounts configured properly.