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

### Instruction:
WHAT SEASON HAD A SEASON FINALE OF MAY 21, 1989 AND WAS VIEWED BY 17.98 MILLION HOUSEHOLDS?

### Inputs:
table_name: table, columns: ['Season', 'Episodes', 'Season premiere', 'Season finale', 'TV season', 'Rank', 'Households (millions)']

### Response:
SELECT MAX Season FROM table WHERE Season finale = may 21, 1989 AND Households (millions) < 17.98