I need to check birthdate in validation rule .

I need to check birthdate in validation rule .If birthdate==01/01/2000 then i need to throw an validation error.

I used below condition but I am getting different error Birthdate=DATE(01,01,2000)

Error while saving record:

Validation Formula "birtdate_Validation" Invalid (Month or Day out of range in DATE() function)'

I need to check birthdate in validation rule .If birthdate==01/01/2000 then i need to throw an validation error. I used below condition but i am getting different error Birthdate=DATE(01,01,2000)

'Error: Validation Formula "birtdate_Validation" Invalid (Month or Day out of range in DATE() function)' while saving record

I need to check birthdate in validation rule .