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

### Instruction:
what is the most recent date founded in elk county?

### Inputs:
table_name: table, columns: ['Park name', 'County or counties', 'Area in acres (ha)', 'Date founded', 'Stream(s) and / or lake(s)']

### Response:
SELECT MAX Date founded FROM table WHERE County or counties = elk county