My benchmark for almost certain vote fraud is an increase over Obama 2008 of about 108%.
Now, in South Carolina, you DO have to take the population increases into account, so we can push the benchmark up to a 110-112% increase for laughs.
This is something that can be addressed by drilling down later, after you've identified The Usual Suspect Counties.
Another point to address is the outlier counties, highlighted in light greenish-blue [Georgetown, Jasper and Kershaw].
Without looking at a map [which is one of the keys to understanding the Democrat vote fraud machine], I can guess that these counties have one of two things true about them:
1. They're embedded in a group of fraud counties [within an hour's driving distance of what I call a central command-and-control county], or
2. They are by themselves a Democrat-dominated county, with a Democrat machine in place to "fortify" the "vote".
Now, I don't know much about South Carolina, so perhaps you can add some comments about the power structures related to those particular counties.
One great visual aid for understanding my spreadsheets and tables is printing out a state map with the counties, then plotting on the map the Joe Biden 2020 percentages where he annihilated Obama's 2008 record turnout.
You can easily see the command-and-control counties on that map.
I understand what you are writing, but one factor not accounted for is Trump himself. He is an incredibly polarizing candidate. Probably more so than anyone ever. He brought out his own voters and voters against him. I think 2020 was all about Trump. No one was going to the polls because they wanted Biden as president. They were going to vote for or against Donald Trump.