Masure to get total invoiced from another table where period is in the same year

[Anonymous]

I have two tables.

Table 1 Invoice:

Table 2 Reminders:

Now i want to create a visual for reminders per year per period. It is the red ones i am having issues with:

Example for one year, (I have data for many years)

Year	Period	Reminder sum	Total invoiced same period	Reminder sum percentage of total invoices
2022	P1	900	3.600	25%
2022	P2	200	400	50%

I have a Date table, so Reminder date and invoice date have a relationship.

I am able to create the first three columns, but for the next columns, i am really struggling.
I have tried to write a measure:
TotalInvoiced=CALCULATE(SUM(tbl_Invoice[Amount]),FILTER(tbl_Invoice,tbl_invoice[Period]=
But i am not able to set tbl_invoice[period] =tbl_Reminder[Period].

Tbl_Reminder doesn't show up as a valid choice. If i hardcode it, it says (translated from Norwegian):

"Cant determine single value for the column 'Period', this can happen when it contains too many values without aggregation, for example min, max, count or sum to get a single result."

[Anonymous]

No they are not related with any relation. 
I am not entirely sure how to relate them, as the invoicenumber only appears once in tbl_Invoice, but it can appear multiple times in tbl_Reminder. 

Period is also a many to many, and i am not sure what to choose if am to relate these?

[DvdH]

Can u show us the ERD? cross out any sensitive information and replace with dummy data.

[Anonymous]

Termin = Period

Fakturadato= Invoice Date

PurreDato = Dunning/reminder date

Following your hint about relationship between these two tables, I created a dummy table, called tbl_Termin (period), and creating a relationship between tbl-Purring(reminder) and tbl_Faktura(invoice), i managet to get the correct data.

[DvdH]

Perfect, I was gonna look at the ERD and check if there was a many:many relation needing a middle dummy table with both unique values from either table. Good that u figured it out. Tag me in any other posts if i can help i will.

[DvdH · Accepted solution]

Hi. This is because u are trying to filter it based on tbl_invoice.period while this is connected to Reminders.
It cannot filter on multiple values in this way.
Are the 2 tables connected with a relation??