OK, this is what I've been able to assess as of today. Originally. This 11 acre tract of land was part of a much larger tract of land, then, sometime in the late 60's, it was sectioned off into several smaller tracts that are now part of the addition in which my son lives.
In the 1920's there was a structure “somewhere” on this much larger tract, hence the reference of “original structure, 1927”. However, this “original structure” could have been anywhere on that much larger tract of land. The current house came much later as part of the breaking the land up into the smaller tracts, hence this explains why so many coins dated post 1960's. But still, no explanation as to why so many and so little trash?
Family reunions, parties, whatever, all of these things would leave traces in the form of trash, I would think. Yet, so far this is by far the cleanest property I've ever hunted considering the amount of coins and obvious activity that took place here. Where are all of the pull-tabs, bottle caps, pieces of foil, etc.? Why has there been no jewelry found, even costume jewelry? No keys, no buttons, etc.?
Wheaties, old Jefferson nickels, these items can still be found in our pocket change and even more so back in the 70's etc., so no real surprise that a few of these are being found among all of the coinage. But I simply can't explain the absence the of everything else, the bottle caps, pull-tabs, pieces of foil, costume jewelry, etc.
So, I think the next time out I'm going to skip the front yard and do a little property roaming to see what pops out of the ground elsewhere. I can always return to the front yard and dig those coins, there aren't going anywhere.
Left knee and back are pretty sore this morning. Getting old SUCKS! 
