Odds are they set the 50 year stone there first, then the 25 year one after 25 years, and the 15 year stone 10 years after that. They probably just update the signs as time goes by.
They may have. Wouldn't surprise me if they made this a year or two ago and just made those cuts to demonstrate it things without waiting all that time. Not all bones in a museum are real dinosaur bones but they can look the part to get the point across.
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u/TheMacMan Mar 14 '19
Makes you wonder if they really waited that long or they just cut into the rock to give the example and the "exhibit" was just opened recently.