In Passing Snapshot - The street signs

Over the years I picked up a habit of photographing various objects in different cities like licence plates, traffic signs and street signs. Some I take for stock, or to remind me of the cities I´ve passed trough etc.
One consideration bout the street signs, something that is merely practical, but in many places they date back decades even centuries, is the way they replace the old with the new. Sometimes they keep the old ones, that as I said before have some historic value, and sometimes they just replace them with the new ones, or with new elaborate ones, and some times, like I´ve seen in south America, they just randomly ad them to the old ones that have´nt fallen off or been ripped off.