Rob, Below is my Sample Data[TABLE="width: 162"]
<COLGROUP><COL style="WIDTH: 51pt; mso-width-source: userset; mso-width-alt: 2486" width=68><COL style="WIDTH: 32pt; mso-width-source: userset; mso-width-alt: 1572" width=43><COL style="WIDTH: 79pt; mso-width-source: userset; mso-width-alt: 3840" width=105><TBODY>[TR]
[TD="class: xl69, width: 68, bgcolor: #4f81bd"]Date[/TD]
[TD="class: xl70, width: 43, bgcolor: #4f81bd"]Value[/TD]
[TD="class: xl70, width: 105, bgcolor: #4f81bd"]Heading2_Code[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]10/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]6[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310ED[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]10/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]17[/TD]
[TD="class: xl68, bgcolor: transparent"]3310FL[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]10/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]33[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310HD[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]10/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]24[/TD]
[TD="class: xl68, bgcolor: transparent"]3310PZ[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]10/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]11[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310RC[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]10/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]0[/TD]
[TD="class: xl68, bgcolor: transparent"]3310SG[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]10/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]7[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310SH[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]11/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]6[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310ED[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]11/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]17[/TD]
[TD="class: xl68, bgcolor: transparent"]3310FL[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]11/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]33[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310HD[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]11/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]25[/TD]
[TD="class: xl68, bgcolor: transparent"]3310PZ[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]11/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]11[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310RC[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]11/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]0[/TD]
[TD="class: xl68, bgcolor: transparent"]3310SG[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]11/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]7[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310SH[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]12/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]6[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310ED[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]12/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]18[/TD]
[TD="class: xl68, bgcolor: transparent"]3310FL[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]12/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]33[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310HD[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]12/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]25[/TD]
[TD="class: xl68, bgcolor: transparent"]3310PZ[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]12/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]11[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310RC[/TD]
[/TR]
[TR]
[TD="class: xl67, bgcolor: transparent, align: right"]12/1/2011[/TD]
[TD="class: xl68, bgcolor: transparent, align: right"]0[/TD]
[TD="class: xl68, bgcolor: transparent"]3310SG[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: #dce6f1, align: right"]12/1/2011[/TD]
[TD="class: xl66, bgcolor: #dce6f1, align: right"]7[/TD]
[TD="class: xl66, bgcolor: #dce6f1"]3310SH[/TD]
[/TR]
</TBODY>[/TABLE]
[TABLE="width: 136"]
<COLGROUP><COL style="WIDTH: 69pt; mso-width-source: userset; mso-width-alt: 3364" width=92><COL style="WIDTH: 67pt; mso-width-source: userset; mso-width-alt: 3254" width=89><TBODY>[TR]
[TD="width: 92"]Row Labels[/TD]
[TD="width: 89"]Sum of Value[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: transparent"]10/1/2011[/TD]
[TD="bgcolor: transparent, align: right"]98[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: transparent"]11/1/2011[/TD]
[TD="bgcolor: transparent, align: right"]99[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: transparent"]12/1/2011[/TD]
[TD="bgcolor: transparent, align: right"]100[/TD]
[/TR]
[TR]
[TD="class: xl65"]Grand Total[/TD]
[TD="align: right"]297[/TD]
[/TR]
</TBODY>[/TABLE]
If i select my data as nov then it must give me the average of (98,99) which 98.5. and similar for other months. That is why i am using sum 1st and then trying and average. to get the values. If i try a direct average it gives me on 14.14 for the above data, which is not the average headcount for all the 3 months.
Do let me know incase you need additional clarifications.