Comment 15 for bug 59060

well I took a look at the code and the changelog, and found out for some questionable reasons, the behaviour was changed from displaying the numeric worth of all investments to a color-trend based on the worth change...

but looking at the code itself revealed, that the calculation seem rather broken:

in the code below, the lines in the iterations should rather read like

  var = row[updater.VARIATION]
  now = row[updater.VALUE]
  start = now - var

to make more sense imho... also the color-scale sensitivity might be a candidate for the preference dialog, as it might need considerable (relative) worth-changes to cause a noticeable color change, depending on the investments done...

(from http://svn.gnome.org/viewcvs/gnome-applets/trunk/invest-applet/invest/widgets.py?view=markup)
class InvestTrend(gtk.Image):
...
def on_quotes_update(self, updater):
  start_total = 0
  now_total = 0
  for row in updater:
   # Don't count the ticker only symbols in the color-trend
   if row[updater.TICKER_ONLY]:
    continue

   var = row[updater.VARIATION]/100
   now = row[updater.VALUE]

   start = now / (1 + var)

   portfolio_number = sum([purchase["amount"] for purchase in invest.STOCKS[row[updater.SYMBOL]]])
   start_total += start * portfolio_number
   now_total += now * portfolio_number

  day_var = (now_total - start_total) / start_total * 100
  color = int(2*day_var)
  opacity = min(0xFF, int(abs(127.5*day_var)))
  if day_var < 0:
   color = COLORSCALE_NEGATIVE[min(len(COLORSCALE_NEGATIVE)-1, abs(color))]
  else:
   color = COLORSCALE_POSITIVE[min(len(COLORSCALE_POSITIVE)-1, abs(color))]

  self.set_color(color, opacity)