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

### Instruction:
How many years for the team with under 31 ties and a percentage of 0.5451?

### Inputs:
table_name: table, columns: ['Mountain West', 'Lost', 'Tied', 'Pct.', 'Years', 'Total Games']

### Response:
SELECT Years FROM table WHERE Tied < 31 AND Pct. = 0.5451