Formula One has changed a lot in the six-and-a-half years since Robert Kubica crashed out of the Rally di Andora in February 2011. Spells of dominance have come and gone, circuits have vanished from the calendar and new ones have emerged. The cars have also changed significantly.
ESPN charts the key changes and statistics of the 2,372 days between Kubica's final 2011 pre-season appearance in Valencia (where he finished fastest) and return to the car on August 2, 2017.
Cars
Weight: Cars have increased in bulk by 88 kg in the time Kubica has been sidelined. The minimum weight of a car in 2011 was 640kg, but that has since climbed to 728kg -- with an extra 26kg added this year alone. This year's bigger, bulkier cars also have added downforce compared to the previous iteration of F1 car, though Kubica would have experienced similar levels in 2008.
Tyres: One thing we never got to see was Kubica managing Pirelli's fast-degrading tyres during a race. The sport turned to Pirelli as sole manufacturer in 2011 as it looked for a way to inject more entertainment into races by ensuring drivers needed to make more pit stops during a race.
DRS: Robert Kubica tested the Drag Reduction System in his final official F1 test session when it had first been introduced, but he has never raced with it on his car. After the 2009 regulations failed to offer the increase in overtaking opportunities F1 had hoped for, rule makers looked for a way to ensure drivers at least had an opportunity to overtake another. DRS was and, to some, remains controversial, but it has stayed in place since 2011 -- the only difference being a driver could use it anywhere on a qualifying lap back then and now it is restricted to DRS zones.
V6 turbos: The most significant change inside F1 cars took place in 2014. Kubica drove during the V8 era, engines which remained until the end of 2013. The following year F1 made a controversial switch to more economical but more expensive and quieter V6 turbos which will remain until at least 2020. This also means Kubica never raced an F1 car with eight gears, something which came with the 2014 change.
Halo/cockpit protection: One of the more recent changes, F1 first unveiled cockpit protection when the Halo was trialled by Ferrari at the start of 2016. Every driver on that year's grid trialled the device, while some have also tested the rejected Aeroscreen and Shield devices. Halo will be on the cars in 2018 -- meaning any return for Kubica could coincide with one of the most significant and controversial regulation changes in Formula One's history.
Wins
Two men have dominated the era since Kubica's accident. Combined, Lewis Hamilton and Sebastian Vettel have won all but one of the championships since and -- as of this year's Hungarian Grand Prix -- have 89 of the 121 wins in that time. It's not difficult to see how, with both men enjoying periods of dominance either side of the introduction of V6 turbo engines. Nico Rosberg, the only other man to have shared Hamilton's successful years at Mercedes, is the last in double figures but has nearly half the wins of his former teammate.
Remarkably, only 13 of those 121 wins have been scored by Ferrari. Mercedes has a staggering 23 more wins than the nearest competitor in this spell, despite Vettel's dominant years of 2011 and 2013. McLaren's statistics are perhaps the most damning, with all 14 of their wins coming before they switched from Mercedes to Honda power in 2015.
There have been just five new grand prix winners in the time since Kubica's departure: Nico Rosberg and Pastor Maldado (2012), Daniel Ricciardo (2014), Max Verstappen (2016) and Valtteri Bottas (2017).
Overall wins since Australia 2011:
By driver:
Lewis Hamilton - 43
Sebastian Vettel - 36
Nico Rosberg - 23
Jenson Button - 6
Fernando Alonso - 6
Daniel Ricciardo - 5
Mark Webber - 3
Kimi Raikkonen - 2
Valtteri Bottas - 2
Pastor Maldonado - 1
Max Verstappen - 1
By team:
Mercedes - 61
Red Bull - 38
McLaren - 14
Ferrari - 13
Lotus - 2
Williams - 1
Pole positions
The pole positions in this period follow a similar trend to victories. Mercedes and Hamilton -- who is closing in on Michael Schumacher's all-time record of 68 -- lead the way. Since the start of 2011, there have been just four new polesitters -- Nico Rosberg (China 2012), Pastor Maldonado (Spain 2012), Daniel Ricciardo (Monaco 2016) and Valtteri Bottas (Bahrain 2017). All of those drivers also registered their first win in this spell.
Overall poles since Australia 2011:
By driver:
Hamilton - 49
Vettel - 33
Rosberg - 30
Webber - 7
Alonso - 2
Maldonado - 2
Button - 1
Massa - 1
Ricciardo - 1
Raikkonen - 1
Debutants
Twenty-nine drivers have made their Formula One debut since Kubica's accident.
2011: Jerome d'Ambrosio, Paul di Resta, Pastor Maldonado, Sergio Perez, Daniel Ricciardo
2012: Charles Pic, Jean-Eric Vergne
2013: Giedo van der Garde, Jules Bianchi, Max Chilston, Esteban Gutierrz, Valttei Bottas
2014: Marcus Ericsson, Daniil Kvyat, Kevin Magnussen, Andre Lotterer
2015: Roberto Merhi, Alexander Rossi, Felipe Nasr, Carlos Sainz, Max Verstappen
2016: Rio Haryanto, Esteban Ocon, Jolyon Palmer, Stoffel Vandoorne, Pascal Wehrlein
2017: Antonio Giovinazzi, Lance Stroll
Of the above, just four (Maldonado, Ricciardo, Verstappen and Bottas) have won an F1 race, while Rossi won the 2016 Indy 500 as a rookie.
Teams
F1 has lost three teams from the grid since Kubica's last test -- HRT, Caterham and Manor-Marussia -- but gained just one, in the form of 2016 debutants Haas F1.
Though Kubica is returning with the same Enstone-based Renault team he was at in 2011, the name and control of the team has changed significantly in the time he's been away. When the Polish driver joined it was the Renault factory team, but the French manufacturer decided to scale back its involvement in late 2010 and sold a majority stake of the team to Genii Capital. It meant Renault was no longer a 'factory' outfit despite the name, but it remained as an engine supplier. In 2011, the grid had Lotus-Renault and Team Lotus (which became Caterham in 2012) due to a legal dispute over the name.
Lotus-Renault became Lotus in 2012, a name it kept until end of 2015, when Renault reversed its decision from the start of the decade and returned to the sport as a fully-fledged manufacturer. The team Kubica tests with is therefore the same as he drove for in 2011, but it has had three name changes in that time and two different owners.
Grands Prix
The idea the F1 calendar has grown wildly out of control in the last few years is something of a fallacy. In 2011, it was supposed to be a 20-race season, but political unrest in Bahrain saw that year's race cancelled, though it returned the following season. With the exception of F1's record-breaking 21-race 2016 season, every year Kubica has missed has featured either 19 or 20 races.
But the races on that calendar have changed slightly. In that time, Austin's Circuit of the America's, India's Buddh International Circuit, Russia's Sochi Autodrom and Azerbaijan's Baku City Circuit have joined the calendar. New Dehli has actually come and gone in that time, joining the calendar in 2011 and dropping off after the third race of its contract in 2013.
India is not the only casualty of the last few years. Turkey dropped off the calendar after the 2011 race, with European Grand Prix host Valencia having its swansong the following year. The Korean Grand Prix dropped off the calendar in 2013. Germany is set to return in 2018 but it is safe to say the Nurburging will not be returning any time soon, with financial difficulties cancelling the German Grand Prix in 2015 at a time when Nurburgring alternated with Hockenheim.