Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
how many winners were in round 8

### Inputs:
table_name: table, columns: ['Rd', 'Race', 'Pole Position', 'Fastest Lap', 'Winning driver', 'Winning team', 'Report']

### Response:
SELECT COUNT Winning driver FROM table WHERE Rd = 8