I easily assumed the OP meant the age of the owners of the layouts.
As one ages, several things can happen:
1} one is no longer ABLE to work on the layout
2} One is no longer able to get around well
3} one is no longer able to accept company
4} One’s spouse is no longer able to tolerate company
5} one is no longer able to get to a layout
6} one has totally lost interest in the hobbby
7} One is has had damage/theft done to their layouts after an open house
8} one is no longer in a financial situation to support a layout
9} FAmily obligations may change {baby sit the grand kids}
10} One may have indeed gone to an assisted living facility
11} one may have moved
12} One may not have the time to entertain those guests seeking to see the layout
13} one may feel one’s layout is “no longer valid”
14} the owner may have died
15} maybe they are building a new layout as they are tired of the same old, same old, old one
16} and to many reasons more than listed here.
So those, and several more mean fewer layouts to view. If you read the thread “withdrawing from the human race” ti tells about damage/theft to a layout on tour…:
http://cs.trains.com/TRCCS/forums/t/196338.aspx
So, for a variety of reasons, some may drop out of the layout tours.
Be happy for those who DO participate, and do not mourn over those who are lost.
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