SUMIF formula help needed

[stitcho]

Hi
I have a SUMIF formula that sums a column between a date range in another colunm which I can get to work fine but once I copy it to another cell and change the date range it breaks. This is the formula:

=SUMIF(STYDate,"=>"&DATE(2011,6,6),STYDuration)+SUMIF(STYDate,"<="&DATE(2011,6,10),STYDuration)

I then copied this to another cell and changed it to this:

=SUMIF(STYDate,"=>"&DATE(2011,6,13),STYDuration)+SUMIF(STYDate,"<="&DATE(2011,6,19),STYDuration)

The first formula works fine but for some reason the 2nd formula ignores the date range and sums the entire contents of the STYDuration column.

Anyone got any ideas? Excel 2003 BTW

 

[stitcho]

If it helps at all I would like to get rid of the &DATE as the date range is specified in the sheet. So for example D3 has the start date and D4 has the end date. I would like to use these instead if possible as my date range as it makes managing the sheet easier

Edit: Ignore this one I have figured it out, still got same problem with the other formulas not working though

 

[stitcho]

Have changed the fomulas to this now:

=SUMIF(STYDate,"=>"&D3,STYDuration)--SUMIF(STYDate,"<="&D4,STYDuration)

AND

=SUMIF(STYDate,"=>"&E3,STYDuration)--SUMIF(STYDate,"<="&E4,STYDuration)

but still no luck
need this pretty urgently as well for reporting. Have made sure all the cells are the correct format, and trimmed off any spaces that might have popped up but still nothing