Homestead-Miami In Perspective

It’s Tuesday, which means putting last Sunday’s Homestead-Miami race into perspective. So here’s a comparison of that race with its historical antecedents. Yesterday’s Race Report gives more details about individual driver performances.

Cautions

Sunday’s race, the twelfth of the season, was a little lower than the average percentage of the race run under caution if you consider the entire run of NASCAR Cup races at the track.

Homestead-Miami in Perspective: A column chart showing the percentage of races run under caution

Given an all-time low of 1.9% and a high of 29.2, the 10.1% of the race run under caution is pretty close to the average value of 13.3%; however, we haven’t seen anything above 13% since 2014.

That’s not too surprising given that, even with additional stage cautions and the larger-than-usual number of competition cautions this year, caution numbers are going down.

Accidents and Spins

We can hardly blame the drivers for competition cautions and stage-end cautions, but they are the ones we must look to for accidents and spins. Here’s a breakdown of accidents and spins over the history of Cup-level racing at Homestead-Miami.

Homestead-Miami in Perspective: A column chart showing accidents and spins from 1999-2020

I’ve normalized the numbers to a 267-lap race to make them appropriate to compare. We only had one accident and one spin at the 2020 race, with two cars involved in the accident and one in the spin. (Of course, they don’t keep statistics about crashes on pit road, which did play a significant role in this race.)

Leading, Finishing and Passing

Let’s start by looking at how many drivers finished the race and how many finished on the lead lap.

Homestead-Miami in Perspective: Boxplots showing the percentage of cars finishing the race and finishing on the lead lap

The median number of cars finishing the race (right graph, above) is around 90%. At this race, 97.4% of the cars finished the race. The only one we lost was J.J. Yeley in the 27, who completed most of the race, but eventually was taken out by a failing fuel pump.

Slightly fewer cars finished on the lead lap (39.5% or 15 cars compared to a median of about 44%. A number of good drivers had problems on pit road, which contributed to their getting one or more laps down. Given the lack of cautions, there weren’t many chances to make those laps up. Eleven drivers (29%) finished one lap down.

Margin of Victory

Homestead-Miami in Perspective: Boxplots for leading, winning and passing

The margin of victory was less than a second, well below the 1.4 second median. That places it at the low side of a ‘normal’ race. But note that Homestead-Miami is one of the few tracks that has a lot of outliers, with races having been won by as much as 7+ seconds.

The other two quanties shown here were pretty much at the median for this track.

Lead Changes

I break lead changes down into yellow flag, green flag, and green-flag-on-a-restart.

A column chart breaking out lead changes to green flag, yellow flag and restarts

I’ve shown that there are often a lot of lead changes when there are a lot of cautions because the lead changes as people make pit stops, and there is a restart for every caution, thus more changes to take the lead on a restart.

Out of 17 lead changes, 8 were during green-flag racing. Four more took place during restarts and 5 during yellow flags.

Quality Leaders

Quality leaders are those who lead 2 or more laps under green, which eliminates those drivers who only lead laps during pit stops.

Homestead-Miami in Perspective: A column chart showing leaders and quality leaders

There were seven leaders, five of which are considered quality leaders according to my definition.

The median number of quality leaders at Homestead is six (std dev = 2.09), so we’re well within the expected range. The median number of non-quality leaders is two (std dev = 1.60)

Green Flag Passes per Lap

Turning our attention away from the leaders, the average number of green-flag passes per lap was 13.4, which is identical to the last race at Homestead-Miami.

Homestead-Miami in Perspective: Average Green-Flag passes per lap, showing in a column plot

The average number of green-flag passes per lap at Homestead-Miami is 13.24 over the 1.5 mile track.

So there it is: Homestead-Miami in perspective. This was a pretty average race for Homestead.

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