Spring 2021 Charlotte Race Review

The Spring 2021 Charlotte race featured only four cautions — and two were stage cautions. Hendrick Motorsports dominated the race and set a new record for wins by owner.

Caution and Lead-O-Gram

As usually, the first thing we’ll examine are the caution- and lead-o-grams for 2021 Spring Charlotte. The caution-o-gram is pretty boring given that we had only fluid on the track and Ryan Newman’s accident. That’s four cautions for a total of 26 laps, or 6.5% of the race run under caution.

2021 Spring Charlotte Caution and Lead-O-Grams showing very few cautions and seemingly a lot of lead changes
Yes, I know Bowman’s name is on there twice. Still haven’t fixed the glitch on this plot.

The lead-o-gram is a little misleading unless you study it carefully. The box score says that we had 23 lead changes and 13 different drivers leading the race.

The weakness of the lead-o-gram is that green-flag pit stops make much bigger differences than they normally do.

Lead Change Types

There were four rounds of green-flag pit stops, and each was very spread out. Whereas, normally, all the cars stop within two or three laps during a caution, green-flag pit stops at the 2021 Spring Charlotte race stretched out over 7-10 laps. The length of the green-flag pit stops allowed the lead to change more than once during each cycle

A vertical bar graph classifying the different types of lead changes.

The above graph shows:

  • Five drivers led laps only because of green-flag pit stops.
  • Two drivers led laps only because of cautions coming out.
  • Out of our thirteen leaders, only six actually had at least one green-flag lead change
  • 12 of the 23 lead changes happened during green-flag pit stop cycles


Four cautions ties with the fewest cautions for the Coca-Cola 600 in the last 20 years.

A vertical bar graph of the number of cautions in the last 20 years at the 2021 Spring Charlotte race.

The last time we saw four cautions was in 2016, before the advent of stage racing. (NOTE: One of the 2016 cautions was a competition caution, so there were really only three cautions then.) If we eliminate stage and competition cautions, the 2021 Spring Charlotte race was the most caution-free race in 20 years.

With only one accident, we tied 2012 for the smallest number of accidents in the last 20 years, too.

Margin of Victory

Kyle Larson’s MOV was 10.05 seconds, which falls just short of the largest margin of victory in the last 20 years. In 2008, Kasey Kahne won with a MOV of 10.20 seconds.

A vertical bar chart showing the margins of victory for Spring Charlotte races from 2000-2021.

Lead Lap Finishes

Only 15 cars finished on the lead lap, but that’s not so strange for Charlotte.

A vertical bar chart showing the percentage of cars finishing on the lead lap in Charlotte Spring races.

The percentage of cars finishing on the lead lap is usually between 20-60%. The 2021 Spring Charlotte race’s rate of 36.8% is smaller than the last two years, but a lot better than 2018’s 22.5%.

Incidentally, we did pretty well with all cars but one finishing the race running.

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