Although Hot Wheels diecast models do have a date on their underside that is actually the copyright date for the Hot Wheels design for the car (more specifically the base). Also on the base of all Hot Wheels models made from 2008 onwards is a date or "base code", starting with a letter followed by two digits, this is what you need to enter here. If your Hot Wheels model doesn't have one it was most likely made before 2008.
Hot Wheels Date Code:
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