Help with formula to sum numbers prior to date

[ExcelAtEverything]

Hello,

I was hoping to get some assistance as I'm having trouble with this. Using my table below as an example, how could I write a formula which will basically say:

* For each store, add all monthly dollar amounts for months that occur prior to the month of the "Reporting Date" in $B$2. (or in this case, Jan & Feb)

*For the month in the table which is equal to the "Reporting Date" in $B$2 (in this case, March), I would like to take the daily average of the dollar amount shown for that month (divided evenly by # days in that month (in this case 31)), and multiply by the number of days that have passed so far in the "Reporting Date" $B$2 (specifically up to but not including the "Reporting Date"). In other words using the displayed table, for the month of March (since that's a partial month due to the "Reporting Date"), Instead of entering $100, I would only enter $87.21 (since that is an estimated amount based on the "Reporting Date".

Thank you.

 

[ExcelAtEverything]

Oh I see. You are close. Since the report date is the 3/28, it needs to include only up to the 27th, and not include the 28th. You are including the 28th in your calculation. The report date assumes it is the morning and you are running all the sales reports for the prior day. So if the report date is the 28, you would not yet have the numbers for the 28, because it would be the morning of the 28th. Make sense?

 

[Andy Pilkington]

The single day adjustment is an easy fix but if the other results are what you are looking for I can share the spreadsheet with you. What I have sent to you shows only the information which I have assumed you really want to see. The formulas I have kept on a separate worksheet so that it can be protected and not be allowed to confuse your working data.

 

[Fluff]

Does this do what you want

+Fluff 1.xlsm
	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P
1
2		25/03/2021
3
4		To Date		Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Total
5		327.419355	Loc1	100	150	100	150	150	160	170	180	190	200	210	220	1980
6		604.83871	Loc2	200	250	200	250	260	270	280	290	300	310	320	330	3260
Results

Cell Formulas
Range	Formula
B5:B6	B5	=SUMPRODUCT((MONTH($D$4:$O$4&1)<MONTH($B$2))*(D5:O5))+INDEX(D5:O5,MONTH($B$2))*(DAY($B$2)-1)/DAY(EOMONTH($B$2,0))
P5:P6	P5	=SUM(D5:O5)

 

[Snakehips]

Does this help?
You need to ensure the year applicable to data is in C1. That will generate correct end dates in C2:O2

Book1
	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R
1	Report	Data Year	EOM	EOM	EOM	EOM	EOM	EOM	EOM	EOM	EOM	EOM	EOM	EOM
2	28/03/2021	2021	31/01/2021	28/02/2021	31/03/2021	30/04/2021	31/05/2021	30/06/2021	31/07/2021	31/08/2021	30/09/2021	31/10/2021	30/11/2021	31/12/2021
3
4			Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Total		To Date
5		Loc1	100	150	100	150	150	160	170	180	190	200	210	220	1980		337.0968
6		Loc2	200	250	200	250	260	270	280	290	300	310	320	330	3260		624.1935
Sheet1

Cell Formulas
Range	Formula
D2:O2	D2	=EOMONTH("01/01/" &$C2,COLUMNS($D:D)-1)
P5:P6	P5	=SUM(D5:O5)
R5:R6	R5	=MIN(P5,SUMIF($D$2:$O$2,"<"&$B$2,D5:O5)+INDEX(D5:O5,MONTH($B$2))*(DAY($B$2)-1)/DAY(EOMONTH($B$2,0)))

 

[ExcelAtEverything]

Something seems to be off. It is returning a #value error. A few things:

1) Row #2 pasted in with hyperlinks and formatted to General, so I removed hyperlinks and reformatted to a short date format.
2) "2021" formatted as General (when I try to change it to custom or date, it changes to that 01/01/1900 logic.
3) I broke apart the formula so I could follow what you are doing, but I'm having difficulty because each part that I test on it's own seems like it comes back as an error or "0" except for this part (...SUMIF($D$2:$O$2,"<"&$B$2,D5:O5)... which returns "$150". And even that seems incorrect, as this appears to be the part that is tallying the completed months that have passed... yet it skips January and only includes February. Most or all other arguments either return "0" or an error message.

Am I doing something incorrectly?

 

[ExcelAtEverything]

Thx Snakehips! I was able to get it working! & Fluff too! ?