SumProduct multiple criteria with text - arrays

Question

I have a bank register on the left. I want a code on the right to tell me sum all the times the description "Rent" is paid in that month. I've tried index, sumproduct and sumif. I can't find the correct way to have it search by month, year and text.

Answer 1

It isn't clear what format your tables are in.
SUMIFS is the easiest solution but it will only work if the bank register uses the Excel date format. It gets a little complicated if those dates are formatted as text.
Building a SUMIFS formula begins with the SUM RANGE. This is a welcome change away from the backwards construction and wrongly named SUMIF (looks more like an IFSUM if you ask me)
=SUMIFS(SUM RANGE, CRITERIA 1 RANGE, CRITERIA 1, CRITERIA 2 RANGE, CRITERIA 2, CRITERIA 3 RANGE, CRITERIA 3...)
Using your example:
SUM RANGE, the 'Debit' column of the bank register (BankRegisterDebitRange)
CRITERIA 1 RANGE, the 'Description' column of the bank register (BankRegisterDescriptionRange)
Criteria 1, the string "Rent"
Criteria 2 Range, the 'Date' column of the bank register (BankRegisterDateRange)
Criteria 2, this formula string ">="&EOMONTH(RentTableDate,-1)+1
Criteria 3 Range, the 'Date' column of the bank register (BankRegisterDateRange)
Critera 3, this formula string "<="&EOMONTH(RentTableDate,0)
Putting it together:
=SUMIFS(BankRegisterDebitRange, BankRegisterDescriptionRange, "Rent", BankRegisterDateRange, "=>"&EOMONTH(RentTableDate, -1)+1, BankRegisterDateRange, "<="&EOMONTH(RentTableDate, 0))
If your data is fornatted as text then you need to decide if you want to use helper column or not or if you want a single formula. A helper column may be desirable if you want to use SUMIFS or perform additional analysis with simple formulas. A different array based formula may be desirable if you don't want a helper column, for example SUMPRODUCT or SUM.
There's already great answer showing how to use SUMPRODUCT so here is an example of how to build an array formula with SUM when your data is fornatted as text.
=SUM((BankRegisterDebitRange)*(BankRegisterDescriptionRange="Rent")*(DATEVALUE(BankRegisterDateRange)=>(EOMONTH(RentTableDate,-1)+1))*(DATEVALUE(BankRegisterDateRange)<=MONTH(RentTableDate,0)))
This is a true array formula and must be entered with Ctrl + Shift + Enter
I was surprised by some of my results during testing. Mainly how Excel was still treating text as dates in some cases but not others. For example, DATEVALUE was needed on the bank register side but that wasn't the situation with the rent table because EOMONTH worked just fine without it. I believe it is related to another odd behavior: when I create a text formatted cell in A1 and then enter a date, regardless if it is preceded by an apostrophe or not, then if I enter =A1+1 in any other cell, that cell becomes formatted as text and displays Excel's numerical value of the day after the date in A1. What I expected was a #Value! error. I suspect this is what keeps EOMONTH from bonking and the mysterious nature of arrays somehow preventing that behavior from carrying over to SUMIFS... but I really do not know why this is happening.

Answer 2

Suppose you have the following named ranges:
BankDate being the date column in your bank register table;
Desc being the description column in your bank register table;
Dr being the debit column in your bank register table.
If the look up date are text, you can use the following formula:
=SUMPRODUCT((Desc="Rent")*(TEXT(BankDate,"mmm yyyy")=G2)*Dr)
If the look up date are date, you can use the following formula:
=SUMPRODUCT((Desc="Rent")*(TEXT(BankDate,"mmm yyyy")=TEXT(G4,"mmm yyyy"))*Dr)
Change G2 or G4 in the above formulas to suit your actual case.
The logic is to use TEXT function to convert the BankDate into the same format as your look up date, and then use SUMPRODUCT function to return the rent by month.
Ps. using SUMPRODUCT may be an overkill, as SUMIFS suggested by #ProfoundlyOblivious is actually faster in excel calculation.
Ps2. as pointed out by #ProfoundlyOblivious, there is an interesting behavior in Excel in terms of treating text date as 'real' date in certain scenarios. Although it may not be relevant to the question of this post, I'd like to share some of my test results here for anyone interested: