how to: have something equal Cx where x=8+ C4

[Raget]

Hi,
I am sure there is a really simple solution to this one.
I have a cell that equals an average, eg =Average(C5:C10), which i have
filled for about 400 rows. I want to easily have one cell where i can edit a
value, say from 5 to 10, which would then increase the difference between C5
and C10 to C5 and C15. I am pretty new to excel, dont have much of an idea,
but i would like to avoid having to refill every time i want to change that
value.
I attemped =average(C5:C(5+A1)) where A1 equaled the value, but that just
returned with an error.
Any help is appretiated

 

[Max]

Try: =AVERAGE(INDIRECT("C5:C"&A1))
where A1 will house the row number

 

[T. Valko]

Another one:

=AVERAGE(C5:INDEX(C:C,A1))

A1 = 10

The formula will average C5:C10

If A1 is empty the entire range will be calculated.

 

[Raget]

Hi,
Yeh, that worked kind of, but i cant switch the two around. My original post
was incorrect. I wish to have a series of numbers, and to have next to each
number, the average over the past x ammount of numbers, but i dont want to
have to change the cell and fill it everytime. So it would be something like
(to use my old and non-working example) =average(C(20-A1):C20). and i would
want the A1 to be the number of values it takes into account for the average,
eg, if i were to want 5 numbers A1= 5, thus =average(C15:C20). I would also
want the 20 to automatically change, so that in cell C50, it would be
=average(C(50-A1):C50). I hope i am making sense, sorry for being difficult.
Thanks

 

[Raget]

=AVERAGE(C5:INDEX(C:C,A1)) doesnt quite give me what i need.
is it giving the average from c5 to c(5+A1)? when i edit it, the entire C
column is included? What am i missing here?

 

[T. Valko]

I read your reply to Max but I don't understand what you want. So, if the
formula I suggested doesn't do what you wanted I don't have any other
suggestions to offer.

 

[Raget]

Hard to explain...
There will be a cell - A1. That will be the number of values i want a cell
to take into account when it is doing an average.
So if i wanted 2 values to make the average, i would put 2 into A1, and it
would take into account C5 and C4 when it works out an average to put next to
C5.
If i wanted 5 values, i would put 5 into A1, and it would take into account
C1, C2, C3, C4 and C5 when putting the average next to C5
I have all these values in the C column, so if i were to go down to C20, and
i wanted the average of 2 values (that is, C20 and C19), i would have 2 in A1.
I can do this graphically, with the moving average trend line. If i could
get the values for that that would be the same sort of thing i was looking
for.
Hope that clears things up.

 

[Peo Sjoblom]

How about

=AVERAGE(OFFSET(C5,,,-A1))

 

[T. Valko]

Maybe this:

Assume you have numbers in the range C1:C20

Enter this formula in D1 and copy down to D20:

=IF(A$1=0,"",IF(ROWS($1:1)<A$1,"",AVERAGE(OFFSET(C1,,,-A$1))))

If A1 = 2

D1 = blank
D2 = average of C1:C2
D3 = average of C2:C3
D4 = average of C3:C4

If A1 = 5

D14 = blank
D5 = average of C1:C5
D6 = average of C2:C6
D7 = average of C3:C7

 

[Raget]

Yeh works great
Thanks everyone for your help,
great fast responses! Im amazed!