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

### Instruction:
What is the highest enrollment schools that joined the mac in 1997?

### Inputs:
table_name: table, columns: ['Institution', 'Location', 'Nickname', 'Founded', 'Type', 'Enrollment', 'Joined MAC']

### Response:
SELECT MAX Enrollment FROM table WHERE Joined MAC = 1997