laregest 30 consecutive average of values in a 180 cell range

[mreynolds1775]

Good morning all,

I am looking to find the highest 30 day average of sales within a 180 range. I already track total sales by month, but as an example, this doesn't work as an accurate depiction. Example: first half of Aug sales were low, second half were high; first half of September sales were high, and the second were low. The period from mid august to mid September was the highest sales period.

any clue how to find this info? thanks in advance.

-Mike

[Pecoflyer]

Please post a sample sheet with some data and expected results - Thx

[mreynolds1775]

Peco,

Thanks. Please see attached example. Highlighted cell represents the desired result. I want this to be an automated so that I can determine worst case scenario for demand of an item.

Initially, I had thought that using =average(Large(range{1,2,3,4,5,...30})) would do the trick, but that will give me the average of the 30 highest days of sales, not the highest 30 days of sales....make sense?

-Mike

[ArviLaanemets]

I can see only 2 possible solutions:
1. A VBA script which reads 180 days data into array, and runs a 150-step cycle, calculates an average (there is a shortcut when you save before the first value in cycle, so you can deduce it in next cycle and add a new last value instead) for every step, and when this is more than max average until this step, saves the new max value into variable(s) or another array (probably you need period start and end dates too), or into predefined Name;
2. A separate table with columns PeriodStart and PeriodEnd which are calculated for first row as (TODAY() - 180 +ROW() - X) AND (TODAY() - 180 + ROW() - X) + 30, where X is the number of row for 1st period. For every next row, the period shifts 1 day, and you'll have 150 rows of data in this table. In 3rd column, average for period is calculated from your data table (Using SUMIFS() formulas). And then you can calculate max average using MAX() function on column with averages (calculate it as Name - then it will be much easier to use it in formulas).

[xor]

I am not sure, but you can try to take a look at row 14 in the attached file.

Cell B14 shows the average sales for first 30 days, cell C14 shows average sales for 02-jan-17 to 31-jan-17 and so on.

[Pecoflyer]

Originally Posted by mreynolds1775

but that will give me the average of the 30 highest days of sales, not the highest 30 days of sales....make sense?

Not really

[ArviLaanemets]

My version how to do it

[mreynolds1775]

Originally Posted by ArviLaanemets

My version how to do it

I apologize, but cannot open the zip file on my computer. Any chance in attaching the file direct?

[ArviLaanemets]

OK, it looks like our firewall let it through!

Btw, 7Zip is free, and allows to pack and unpack various formats.

[kvsrinivasamurthy]

If start date is 1/1/17 formula is

=LARGE((SUMIF(OFFSET($B$2,0,ROW($1:$180)-ROW($1:$1),1,30),">0")/30),1)

ARRAY formula is used

To enter ARRAY formula
Paste the formula
Press F2
Press Ctrl+Shift+Enter keys together.
formula will be covered with{} brackets by excel.

[Debaser]

Non-array formula:

=MAX(INDEX(SUBTOTAL(1,(OFFSET($B$2,0,COLUMN($B$2:$ AE$2)-2,1,30))),))