error in formula (averageifs)

hey daniel. the upload attachment must be done by going to Go Advanced. click on Manage Attachments. Choose file, upload and close the window.

one error in your formula lies here:
">="&UC!EOMONTH(H6,0)+1

the worksheet name should be in front of the cell reference:
">="&EOMONTH(UC!C6,0)+1

Although it is unnecessary here because you don't have to reference a worksheet where the formula is residing in. hence, you can go with:
=AVERAGEIFS(LME!$C$4:$C$1003,LME!$B$4:$B$1003,">="&EOMONTH(H6,0)+1,LME!$B$4:$B$1003,"<="&EOMONTH(H6,1))

but the 2nd problem is that cell H6 is empty. maybe it is just a sample file with different references. but if you are referring to 22 Aug, maybe:
=AVERAGEIFS(LME!$C$4:$C$1003,LME!$B$4:$B$1003,">="&EOMONTH(C6,0)+1,LME!$B$4:$B$1003,"<="&EOMONTH(C6,1))

Hello,

This is the formula fragment you posted in your file:

AVERAGEIFS(LME!$C$4:$C$1003,LME!$B$4:$B$1003,">="&UC!EOMONTH(H6,0)+1,LME!$B$4:$B$1003,"<="&UC!EOMONTH(H6,1))

The sheet reference "UC!" belongs in front of the cell, not in front of the function. Also, in your sample file, you probably want to refer to C6, not H6, because that is the cell with the date of 22-Aug.

=AVERAGEIFS(LME!$C$4:$C$1003,LME!$B$4:$B$1003,">="&EOMONTH(UC!C6,0)+1,LME!$B$4:$B$1003,"<="&EOMONTH(UC!C6,1))

In your sample file, this formula returns the value 6,673.81, which is correct according to your sample data.