World record progression 100 metres backstroke

Columns: Time | Swimmer | Date | Place
49.17 | Arkady Vyatchanin | December 12 , 2009 | Istanbul , Turkey | 48.97 | Arkady Vyatchanin Stanislav Donets | December 13 , 2009 | Istanbul , Turkey | 48.94 ( r ) | Nick Thoman | December 18 , 2009 | Manchester , England | 48.92 | Matt Grevers | December 12 , 2015 | Indianapolis , USA | 48.90 | Kliment Kolesnikov | December 22 , 2017 | Saint Petersburg , RUS | 48.88 | Xu Jiayu | November 11 , 2018 | Tokyo , JPN

Example questions:
What nationality is the Men 's World record progression 100 metres backstroke swimmer with a time of 52.71 seconds ? | How many Olympic gold medals did the Men 's World record progression 100 metres backstroke swimmer with a time of 51.28 seconds win ? | How many times has the Men 's World record progression 100 metres backstroke swimmer with the shortest time been named world champion ?

Answers:
Canadian | four | twice