Table:
text: 2012 Formula One season
Grands Prix
Grands Prix
Rd_ Grand_Prix Pole_position Fastest_lap Winning_driver Winning_constructor Report
16 Korean Grand Prix Mark Webber Mark Webber Sebastian Vettel Red Bull - Renault Report
17 Indian Grand Prix Sebastian Vettel Jenson Button Sebastian Vettel Red Bull - Renault Report
18 Abu Dhabi Grand Prix Lewis Hamilton Sebastian Vettel Kimi Räikkönen Lotus - Renault Report
19 United States Grand Prix Sebastian Vettel Sebastian Vettel Lewis Hamilton McLaren - Mercedes Report

Question: How many constructors' categories were there when Mark Webber set the fastest lap in the 2012 Formula 1 season?