Okay, to figure out what's wrong i'd like to check how
 - this post: https://bitcointalk.org/index.php?topic=470453.msg26854986#msg26854986
 - produced this beti chart: https://bitcointalk.org/index.php?topic=470453.msg26855063#msg26855063

Right now things don't add up for me. Please have a look at this: https://i.imgur.com/EOaiYlj.png

I took the beti formula linked in the first post and applied it to two dates:
 - 22-DEC-2017, where both formula and chart produce BETI 0,62 [1]
 - 25-NOV-2013, where the beti formula does NOT match the chart [2]

For me the chart seems not to be produced by the BETI formula. Am I missing something or have we been looking at a flawed chart?

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[1] https://www.wolframalpha.com/input/?i=ln(13441.46)-(+0.00331615547164061++(+december+22,+2017+to+jul+17,+2010++)%2Fdays-0.118770392977885+)
[2] https://www.wolframalpha.com/input/?i=ln(1100)-(+0.00331615547164061++(+november,+25+2013+to+jul+17,+2010++)%2Fdays-0.118770392977885+)