Supercars drivers are two years younger on average this season, and have made 54 fewer starts and won five fewer races, than entering 2017.

That's the overview of the generation shift that has occurred over the last two summers, with the full-time retirements of Craig Lowndes, Garth Tander, Todd Kelly and Jason Bright.

Kelly and Bright bowed out of Supercars at the end of 2017, the former not even continuing in the enduros, and have been followed by Lowndes and Tander in recent months.

Between them, the quartet had racked up 1,076 event and 2,415 championship race starts, and a neat 200 race wins.

The likes of Michael Caruso and James Moffat, with nearly 600 race starts between them, have also stepped back to co-driving duties.

Five rookies entered the championship last year, and two more do so for 2019 in Macauley Jones and Garry Jacobson, joining 16 drivers who were on the grid in Adelaide in '17.

All data below only factors in active full-time drivers.

The age game

Even with 16-year-old Alex Rullo in the field, the average age of drivers in Adelaide in 2017 was 32 years and 26 days at the start of the opening race.

That came down to 30 years, eight months and seven days last year, and in 2019 drops again to 30 years and 17 days.

Bright was 2017's oldest driver, turning 44 during the race meeting, a mantle Lowndes took in '18, when he also turned 44.

With Lowndes and Tander no longer on the grid, James Courtney becomes the oldest driver at 38 years, eight months and one day for Adelaide's opener.

At the opposite end of the spectrum, the five youngest drivers this year weren't on the grid two seasons ago.

2017 oldest on day of Race 1 2019 oldest on day of Race 1 Jason Bright: 44 years James Courtney: 38 years, 8 months Craig Lowndes: 42 years, 8 months Mark Winterbottom: 37 years, 9 months Garth Tander: 39 years, 11 months Fabian Coulthard: 36 years, 7 months Todd Kelly: 37 years, 4 months Will Davison: 36 years, 6 months James Courtney: 36 years, 8 months Rick Kelly: 36 years, 1 month

2017 youngest on day of Race 1 2019 youngest on day of Race 1 Alex Rullo: 16 years, 8 months James Golding: 23 years, 1 month Cameron Waters: 22 years, 7 months Todd Hazelwood: 23 years, 5 months Scott McLaughlin: 23 years, 8 months Anton De Pasquale: 23 years, 5 months Chaz Mostert: 24 years, 10 months Andre Heimgartner: 23 years, 8 months Scott Pye: 27 years, 1 month Macauley Jones: 24 years, 4 months

Appearances

At the start of the 2017 season, drivers in the field had contested an average of 120.54 events and 270.96 races.

Just as the passage of time plays a role with driver ages, Supercars has held 30 events and 57 races since then.

Nevertheless, the average number of round appearances comes down to 101, and races down to 217.13.

A sum of 7,045 races across the field is also down to 5,211, albeit based on 24 drivers rather than 26 in 2017.

Lowndes and Tander sit first and second on the all-time round and race start for Supercars, and there's no surprises in the 2017 top four on experience.

A new generation of drivers leads the way now, Rick Kelly, Jamie Whincup and Mark Winterbottom having made their debuts in the 2001, '02 and '03 enduros respectively.

2017 most experienced as of Race 1 2019 most experienced as of Race 1 Craig Lowndes: 264 rounds, 610 races Rick Kelly: 239 rounds, 522 races Garth Tander: 252, 577 Jamie Whincup: 214, 465 Jason Bright: 243, 548 Mark Winterbottom: 212, 470 Todd Kelly: 229, 514 Will Davison: 190, 419 Rick Kelly: 209, 466 Lee Holdsworth: 187, 417

Wins

At the start of the 2017 season, a combined 439 race wins averaged out at 16.88 apiece across the 26 drivers.

This year, 292 across 24 drivers works out at 12.17 each.

Lowndes started 2017 as the Supercars race win record holder, but lost that mantle during the year to team-mate Whincup.

The tables show the win tallies for active drivers at the start of 2017 and '19.

It emphasises the recent run of Shane van Gisbergen and Scott McLaughlin, the pair having started 2017 with 19 and eight victories respectively.