[proposal]

Nothing has changed. 

[And the sales tax has been around 10% historically?]

Do your own research. I am not your librarian.

Here's an article on the GOP proposal for K-12: "GOP proposes major changes in the way Washington taxes and spends on public schools"
http://www.spokesman.com/stories/2017/jan/27/gop-proposes-major-changes-in-the-way-washington-t/