user: Question: How many races were for a distance of 2020 m?
Columns: ['Result', 'Date', 'Race', 'Venue', 'Group', 'Distance', 'Weight (kg)', 'Jockey', 'Winner/2nd']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['5th', '17 Aug 2002', 'Goodwood Sprint', 'Belmont', 'LR', '1300 m', 60.0, 'P. Carbery', '1st - Tribula']
SQL:

assistant: SELECT COUNT("Group") FROM "Table" WHERE "Distance" = '2020 m';