Problems Running Report for Previous Year

[Carlos Astrada]

I did my best to solve this one on my own, but I cannot figure out what the
problem is. Every time I run certain reports (Income Statement, Trial
Balance, etc), either my accounts show a $0.00 balance or most account show
a $0.00 balance. For instance, Income Statement for previous year (dates
selected using manual date  -- i.e. start: 1/1/2006 or Previous Year Start)
shows a $0.00 while the Trial Balance shows SOME account balances for Assets
but nothing for Expenses.

The odd thing is that each account works perfectly, has the correct balance,
and insofar as I've been able to scrutinize, 2007 data / reports work
flawlessly.

Is there something I am missing?

Pertinent info:
GnuCash v.2.0.5
Ubuntu Feisty Fawn
GnuCash file created from scratch (not an import from another program)

-Carlos