I would also note that the data set ends at Obama’s first year in office. What followed was eight years of obstruction and increasingly racist fomentations by the remainder of the Republican Party.
I’ll try to find the 2012 GSS question results, but IIRC, the @5% of the 2008 number had dropped to @3%. The perceived obstruction of Obama did not alter the slope of the decline; one can reasonably assume because the remaining 3% of us who are overtly racist are also elderly. We are just a few years from having virtually no measurable overt racism left in the nation. (Obviously, 1% of 320M people is still 3.2M people, so the KKK and the Spencers of the world will be visible for quite some time. However, statistically, overt racism is nearly gone, from a statistical perspective.)
Regarding, “racism” in the GOP: it is my observation that the US leftists now refer to race-neutral policymaking and speech as “racist.” IOW, if you’re not actively acknowledging racial issues and considering them in your policymaking, you must therefore be a racist. That’s bunk, prima facie.
And that plays on the unconscious racism that can be quickly brought out by crude opportunists such as Trump.
Again, I disagree. I believe that Trump encourages the overt 3% to be more vocal. I do not believe he is creating more overt racists, as you posit. The GSS results in 2020 will confirm or deny what I am seeing from anecdotal sources.
A larger problem with limitations of your data is the large difference in perspective by race. This is where semiconscious racism survives.
This is, in my view, simply a measurement in more detail of what I mentioned before; subconsious racism runs at about a third of the population, and regrettably is NOT declining from Gen Yer to millenial.