averages in excel

[Guest]

i use excel to record students' attendance. i use each sheet for each week
and there are 12 weeks in a course. for every week i calculate the percentage
attendance by using a simple average formula. the 13th sheet is the
accumulative percentage attendance sheet. in this sheet i would like to know
the average of attendance percentage for each student. the catch here is, if
we are in week 4, the average should be for 4 weeks, that is, the total of
percentage attendance is divided by 4, how ever, if we are in week 5, the
average should be for 5 weeks. this means, as each week passes, the number
that is dividing the total percentage should increase automatically by one.
could some one help me with the formula.
thank you
ash

 

[Bob Phillips]

Ash,

To properly help you it would be useful if you described the data. Give a
simple data table of a typical week in time, and how you identify where to
count up to.

If you left the fields to come blank, AVERAGE will work fine, ignoring
blanks. If there is something in there, a simple if(AVERAGE formula should
work.

--
HTH

Bob Phillips

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