Unrealized Gains(Losses)

[Guillaume]

Hi every body.
I try to use the Balance report of Gnucash to calcul the "appreciation" of 
FUND accounts.
In the "Accounts" I select all my FUND accounts
In the "General" I select Nearest in time (prices are updated automaticaly 
from wanadoo)

My problème is that I can't find out how the "Unrealized Gains(Losses)" 
report line is calculated.
I think it should represente de "depracation" and "appreciation" of my FUNDs 
but it doesn't seam to.

Does any one knows how the "Unrealized Gains(Losses)" report line is 
calculated??

Is there an other simple way to calculate depracation" and "appreciation"??

Doesn't Unrealized Gains(Losses) be egal to : current price * shrares less 
(sum of buy - sum of sell) ???

thank you very much.