A couple of months ago, when I first began looking at ways to extract location data from a user-specified location, I was grabbing city, state, county, and zip from the address component array. I should have used the locality, administration level, and postal code type values to help me out, but, for U.S. addresses, I saw that postal code always appeared last, preceded by country, state, county, and city. Using address component array position was a sloppy algorithm which I've changed now, but I'm trying to figure out when the postal_code_suffix was added on a large-scale basis.
It seems that just in the past month or so, most U.S. locations queried now come back with a last address component of postal_code_suffix and the 4-digit code that is optionally appended to zip codes.
My question is, when was ZIP+4 (postal_code_suffix) adopted on a widespread basis for U.S. addresses within the Google Maps API? I can't find anything on the Google Maps API site. This Stackoverflow answer implies that ZIP+4 was not implemented as of March 2013
I want to be able to provide the customer with a specific time-frame in which errors began happening. (The last element of the array is no longer ZIP in most cases).
I realize this question is not particularly technical in nature, but the Google Maps API discussion forums direct users here, and I have looked extensively elsewhere for an answer.