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

### Instruction:
Name the number of reason for change on may 11, 1939

### Inputs:
table_name: table, columns: ['District', 'Vacator', 'Reason for change', 'Successor', 'Date successor seated']

### Response:
SELECT COUNT Reason for change FROM table WHERE Date successor seated = May 11, 1939