The Caution/Lead-O-Gram is my attempt to capture a race in one graphic.
Cautions
The cautions are show in the top section, along with their cause. In 2022, I started analyzing each caution because NASCAR lists the reason for the caution, which isn’t always the same as the cause. That’s why you’ll see tire issues and wheel issues listed.
Tire issues are listed as the cause when I’m positive that tire failure caused whatever happened to bring out the caution flag. If a driver flattened a tire by hitting the wall, that’s an accident.
The graph is plotted by laps so that it matches the graph below it.
Lead Changes
The lower graph of the Caution/Lead-O-Gram shows who led which laps. I have recently been trying to separate earned leads — those that come about from positive action of a driver — from unearned leads. In my nomenclature, unearned leads are those that result from another driver doing something.
For instance, let’s say that Chase Elliott is running P2 and Kyle Larson is running P1. Larson pits. Elliott inherits the lead. Elliott didn’t pass for the lead, so that’s an unearned lead.
I count taking the lead on pit road as an earned lead.
Unlearned leads are shown with hatches. That’s not always the clearest when there are a lot of leaders, so you might need to look at the table to see the details.