jimomura@lsuc.on.ca (Jim Omura) (06/24/91)
I've been working with the Calculator function of the Portfolio
a bit now, and I'm looking at the "Markup" and Markdown" functions.
It seems to me that the keystroke sequences used for these are probably
not a good idea. In essences, the keystroke series
100*10%=
will give you 111.11
The problem is that "100 times 10 percent" is a well known mathematical
relationship which one would expect to yield an answer of 10 rather
than 111.11.
The formula that they are representing by this is
price = (cost * 100) / (100 - n)
where "n" = the nominal %
Similarly the keystroke sequence
120/15%=
will give you a result of 104.34 rather than the "800" that you might
expect. Here the formula they are representing is
cost = (price * 100) / (100 + n)
where "n" = the nominal %
There are a lot of people who would not work with a "markup"
or "markdown" calculation on a regular basis. Even having this
information in the manual, it would be easily forgotten, making
errors possible, particularly in long complex formulae where the
error could be hidden. I think it would have been better to
use use a more distinctive and not "well known" keystroke pattern
for these formulae. I'd suggest "MU" for the "markup" and "MD"
for the markdown.
--
Jim Omura, 2A King George's Drive, Toronto, (416) 652-3880
lsuc!jimomura
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