RD calculation based on No.of weeks,days,months,years

Will you please attach a sample Excel workbook? Please don't attach a picture of one.

1. Make sure that your sample data are REPRESENTATIVE of your real data. The use of unrepresentative data is very frustrating and can lead to long delays in reaching a solution.

2. Make sure that your desired solution is also shown (mock up the results manually).

3. Make sure that all confidential information is removed first!!

4. Try to avoid using merged cells. They cause lots of problems!

Unfortunately the attachment icon doesn't work at the moment. So, to attach an Excel file you have to do the following: Just before posting, scroll down to Go Advanced and then scroll down to Manage Attachments. Now follow the instructions at the top of that screen.

ALSO: PLEASE DON'T CREATE DUPLICATE THREADS. This has the potential to waste our time.

How much of this is an Excel question, and how much is math/finance?

A quick internet search finds these two pages:
https://en.wikipedia.org/wiki/Recurring_deposit
http://www.rdcalculator.co.in/formul...e-rd-interest/
These two pages present the equations for RD. The equations seem simple enough. And with a little bit of algebra to change the time units on n, it should be fairly straightforward to come up with the formula for whatever base time unit you want.

If you have already done the algebra, helop us understand the resulting formulas, and we should be able to help you program those into Excel. I note that the formulas require nothing more than simple addition/subtraction/multiplication/division which are represented in Excel by the standard +-*/ operators. You may want to explain exactly what you are having trouble with, as this seems like it should be very basic once the algebra part is done.