Most specifications for the Fender guitars are hardly changed.
Although there have been periods in which major changes occurred as the acquisition of Fender by CBS, and the transition from CBS Fender to the current owner (Fender Musical Instruments Corporation), most models are in general not changed.
As you can see by the overlap of numbers and years, the reference to the actual date of manufacture is rather vague.
In 1990, the N came as a prefix to the numbers, which stands for the nineties. Deluxe Series have the same standard but with the addition of a D for the Z, eg. Also here some overlap of numbers, prefixes and year.
(Stratocaster) Between 19 there were periods that this is not consistently done.