Need budget formula help

Killing my brain on trying to make this work....

Attached is a very simple breakdown I am using for an example (nice round numbers)....the attachment button and pic upload are not working, so pic link below.

Top left: You see a "budget", "spent", and "remaining"......so easy numbers....I had 3k, spent 2k, and now have 1K left.....our budget runs from the 15th of current month to the 15th of the next month....so, easy math here, I have $250 per week to spend (as you see below it)......here comes the hard part...

What am I am trying to calculate is.....if I do not spend anything in week 1 ($250)....I want that extra $250 to then be divided by the last 3 weeks......if I also do not spend the 2nd week's $250....again, spread that over the last 2 weeks....

If I have a balance left in week 4, that will now be added to my beginning budget for the new month.

The part I am stuck on is, I guess I will need some kind of date field to calculate what is defined as week 1, 2, 3, 4

Let me know if I confused you enough.

http://i66.tinypic.com/14m5f9y.jpg


Thank you in advance!

Ah thanks! Here is the attachment.

I was able to figure it out...thanks for the fast responses.

The solution I came up with was:

Remaining budget / 4 = my starting point...in my example, this was $1,000 / 4 = $250 per week.

Then I put my end date (the 15th of next month) in another cell, the formula =TODAY() in the cell next to it and added a simple subtraction.

So each time I opened the workbook, it would recognize today's date,and then subtract the number of days left in the 4 weeks...

So my start date (as of today) is 11/28/17...my end date is 12/15/17 = 17 days left in the fiscal month. That equals 2.4 weeks.

Finally, took my remaining budget that has not been spent / 2.4 weeks....now shows how much weekly I can spend.

Since I had not spent all of my budget, I now show $353 per week to spend vs $250 when I started since the month is rolling along.