G

#### Garbin

I have a spreadsheet containing data representing a 3 dimensional data

structure in the following form;

Z1 Z2 Z3 Z4 ...

Y1 X1 X1 X1 X1

Y1 X2 X2 X2 X2

Y1 X3 X3 X3 X3

Y1 X4 X4 X4 X4

Y2 X1 X1 X1 X1

Y2 X2 X2 X2 X2

Y2 X3 X3 X3 X3

Y2 X4 X4 X4 X4

Y3 X1 X1 X1 X1

Y3 X2 X2 X2 X2

Y3 X3 X3 X3 X3

Y3 X4 X4 X4 X4

.... ....

and so on

In other words for every value Y (of which there are 8800 in total) there

are four X values and I have one set of data (8800 x 4) per month (with nine

years of data in total), so 3,801,600 data items in total (8800 x 4 x 12 x

9)

What I would like to do is average the four X values for each value of Y and

re-display it on a new sheet something like...

Z1 Z2 Z3 Z4 ...

Y1 Xm Xm Xm Xm ...

Y2 Xm Xm Xm Xm ...

Y3 Xm Xm Xm Xm ...

Y4 Xm Xm Xm Xm ...

..... ... ... and so on

However, when I construct the first line of the new file and then try to

drag it I don't get the right results i.e. if the first value of Xm is given

by AVERAGE(B1:B4) and the second is given AVERAGE(B5:B8), I actually get

AVERAGE(B2:B5). Even when I construct the first two lines of the file and

drag it I still don't get the right answer. How can I achieve this simple

action without having to resort to VBA? I'm sure I'm missing something

really obvious, so if I'm being a total noob please tell me

Thanks in advance

Ian