Yes - the 5s and 10s are part of our magical thinking caused by
   being raised with a base-10 math.* They're easy to do, we like
   them and.. they're kind of magical:* in our heads, we can do
   10000 + 10000 as easily as 1+1 :P*** It's not a bad thing but
   yeah the pattern of 10s in the data I kind of expected but I'll
   definitely check out the link because I always love learning
   more. Certain numbers do seem to have magical qualities for
   various reasons, many perhaps culturally based.* 17 is
   significant in American data it seems, but data pull has 17 as
   being similar to the surrounding numbers.* Different area of the
   world, different cultural expectations.* That's kind of where I
   was edging towards; the cultural bias of this which is why I
   *really* appreciate sreejith's duplication. from a different
   place. 3 is an interesting case as well.* *Is* there something
   that "happens at 3*?* I learned in child psychology that
   "fantasy thinking leads to concrete thinking between the ages of
   3 and 4"... but is that really so? I've accepted that as I was
   taught it,* but honestly, if anything, an increasing awareness
   of the BS around them seems to be taking place more than
   anything, with a greater and greater ability to comprehend and
   utilize it successfully. Still, there *seems* to be something
   that happens around 3-4 yrs old, and something else around 8-9:
   cultural? biological?* I don't know.* But whatever the source,
   the importance of peers seems to dominate beginning around the
   age of 7, the chattering, the rumor-passing, the slander, the
   great shames and the awesome triumphs... it is a very dramatic
   age yet often a drama either self-contained or restricted mostly
   to "kid world". Yet at the same time, a great confidence at
   facing the adult world head on ALSO seems to happen:* The nature
   of defiance changes often, either into bold confrontation
   without backing down... or agreement with a smile while doing
   what you want anyhow while *also* being fully aware of the
   consequences... all happening simultaneously.* Not in all cases
   but in many it seems.* I remember being a part of it myself,
   seeing it around me.* I feel in some ways, I was my smartest in
   4th grade (not grade-wise but confidence) with ups and downs
   iterating since then - but that's definitely the beginnings of
   my self-awareness that at its core, hasn't changed much through
   the decades. Before 7?* Mish-mosh of images although many solid
   memories there too.* But not the sense of "I AM KENNETH UDUT";
   it was more of a "this is right and wrong but I really don't
   know why".* Around 7, I knew why and by 8 and 9, I would tell
   anybody who asked - even if they didn't ask.* I really haven't
   changed :D