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

### Instruction:
What year had a date of TBA where the Oakland raiders were the home team?

### Inputs:
table_name: table, columns: ['Year', 'Date', 'Television', 'Designated Visitors', 'Designated Home', 'Stadium', 'City']

### Response:
SELECT AVG Year FROM table WHERE Date = tba AND Designated Home = oakland raiders