Summarizing partial data based on date range

Is there a way that I can build a function that will look at only a certain date range, even though my spreadsheet may have more data available? I am trying to compare, day by day, how the departments revenue for 2012 compares to what it was in 2011. I have a spreadsheet that has the 2011 data populated, but since all of 2012 hasn't happened yet, I only want it to compare to the beginning of the month through yesterday. Currently, I am doing it by manually changing my sum ranges each day - it would be nice if I could change one field and it automatically recalculate.

unless i am way off base, the solution is as simple as using a SUMIF.

=SUMIF(D2:AF2, A2<>2012)

I need it to sum up the partial 2011 data (through yesterday's date) and compare it to the existing 2012 data. I was originally summarizing it via a pivot table using the total lines on the data I sent you. I am trying to avoid changing the formula every day. I was hoping to come up with a way that it either knew what the date was for yesterday, and then summarize everything from the 1st of the month through yesterday's date, for both years (even though for 2011 I have data through the end of the month in my data file.

Thanks!