Re: [office-formula] YEARFRAC/Basis in more detail

[Eike Rathke <erack@sun.com>]

Hi David,

On Friday, 2007-05-25 17:02:32 -0400, David A. Wheeler wrote:

> One of the three main comments we got back on the formula spec was
> that "Basis"/YEARFRAC wasn't defined in enough detail.  When the test
> cases get removed, it'll be much worse.  In this case, I believe we
> should take the Excel values as "canonical" unless shown it should NOT
> be otherwise... but I've found NO place that actually defines it.

As Andreas already mentioned, the values differ in different releases of
Excel. What we could do though is to compare a separate (own)
implementation of the algorithms described in the ISDA market
conventions http://www.isda.org/c_and_a/pdf/mktc1198.pdf with results of
Excel 2003 or later, assuming they were correcting things in 2000
instead of worsening.. If identical, which hopefully will be the case,
we could be pretty sure and digest some neat definition from that ISDA
document's formulas.

  Eike

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