pull information from a field in another table from the respective field based on the month of the year

You can set the Key field of your interest rate table to be a date field of the first of the month. Then in your detail table make a formula field of

FirstDayOfMonth ([My date field])

Them use that to make a relationship to the interest rate table and the lookup the interest rate.

Hey Mark,

Thank you so much for your help. I dont think i was able to accomplish what you said.
I made a quick 1 minuto video to explain better what I am trying to do here. If you or anyone could help me figure the best way to do this, It would be very much appreciated.

Sergio

I read your question again.

The best way to do the tables is to have a separate record for each month in the interest rates table. Set the key field to be a date field type and enter the date for the first of the month in each record along with the interest rate.

Thank you! 
I will try again. Really Appreciated! 

Sergio,
Do you have it working now?

Mark, not yet.
I think there is something missing.
Its probably easier for you to understand if you were able to see the video. I dont understand why you cant if I didnt restrict the region.

Anyways, I created the records, one for each month with the interest rate for each month.

In the other table where I have the transactions, each transactions has its value, and its interest rate according which month it is. 
What I needed is if I have 100 transactions on Jan, the interest rate would be whatever the interest rate it is on the interest rate table. 

Right now the way I do is, change the default value of that field in the begining of the month, so every record I import after that date, will have that default value on the rate.

Even the guys on the quickbase support team were not able to get that working for me.

Sergio
I did watch the video via the link you posted.

What you want to do is very simple, so it will work.

Please answer these questions.

1.  Do you have a table of Interest rates, with 1 record per month.

2. Is the key field a date field?

3. Is that Key field loaded with the 1st of each month.

4. Do you have a field on the detailed transaction records with a formula of FirstDayOfMonth()

5. Is there a relationship based on that FirstDayOfMonth() field?

6. Are you puling down the interest rate in that relationship?

Hi Mark,

Yes i did. 
I does work for records that have the data of transaction on the first day of the month, but its does not work for the other days.
Dont I need to add something to the formula to pick up the other days?
FirstDayOfMonth([DATE OF TRANSACTION])
It only works for transactions done on the first day, the other days it doesnt work,

No, that is correct.  What field did you use the build the relationship?  Maybe you used the transaction date to build the relationship and not the formula field for the first day of the month.  You need to use that formula field.

Got it!!! 
Works!
Thank you so much!