The biggest changes going into NASCAR this season were the new aerodynamic and engine modifications and how they would affect competition.

Let's face it, NASCAR had a competition problem, highlighted last year with lengthy margins of victory and shrinking number of lead changes and leaders per race.

But the steps they have taken have really worked. It's ridiculous to expect week-to-week photo finishes, but the racing is tight, passing is up and excitement has followed this rules package, especially on the intermediate tracks, which were recently, quite honestly, total snore-fests.

I'm not going to just tell you they're better though. I'm a numbers guy, so here are some numbers.

The proof's in the passing

Last year, Kyle Busch dominated the 600-mile race at Charlotte, leading 377 of a possible 400 laps. This year's winner, Martin Truex Jr., led just 116 laps, but it goes deeper than that.

There were only nine lead changes over the 400 laps last year (or one every 44.4 laps). The 2019 version of the race had 30 (or one every 13.3 laps).

Those 30 lead changes were the most at a track other than Daytona or Talladega since March 2015 at Martinsville. It was the most at any 1.5-mile track since the October 2014 race at Charlotte.

Overall, there have been 19.8 lead changes per race this year, up 30 percent from last year's 15.3 per race.

And just back to looking specifically at the 600, according to NASCAR's loop data, there was 3,929 green flag passes in the race. That total is also up 29 percent from last season's total.

And we're seeing a variety of cars at the front. Sunday's race was the fourth straight with at least 10 different leaders. It's the first time that's happened in the last three seasons.

Keeping it close

The margin of victory of Sunday's race was 0.330 seconds, with Truex Jr. beating Joey Logano to the line.

Since NASCAR began electronic scoring in 1993, that's the third-closest we've seen in 48 races that ended under green in that time. Both of the closer races took place in the 2005 season, with Jimmie Johnson getting the victory in each.

It's the second straight race and sixth time this season that the margin of victory has been under a half-second. Last season, there were only 10 such races out of 36, a "close finish rate" of 28 percent. This year, it's 46 percent.

Overall, the average green-flag finish this season has had an average margin of victory of 1.54 seconds. If you take out Truex's nine-plus second victory at Dover, it's .816 seconds.

Still, that 1.54 seconds trims nearly a half-second off last year's average margin of victory.

And if we were to get back closer to the .816 average that we have without Dover, that would be just the second time in the electronic scoring era (since 1993) that the average margin of victory was under a second. It also happened in 2014.

So, even if Sunday was another Joe Gibbs Racing victory (and another Team Penske strong run), rest assured the competition level is definitely moving in the right direction.