Calculating Future Value but with contributions and deductions at different frequencies

[JR73]

Hi there,
I know about the FV function but I was hoping to get help with a more complex formula to be able to calculate the future value of an investment if quarterly contributions are added as well as annual amounts deducted. The real world scenario is: I have an initial capital amount (A) which is invested at a compound annual growth rate of (r) percent for (n) years. Each quarter a set amount is added to the investment by way of the Australian compulsory employer Superannuation Guarantee (SG) contribution scheme. Then once a year all the profits on the investment as well as the 4 x SG contributions are taxed at 15% and this tax amount is then deducted from the investment. I know how to calculate the future value of my investment with either the deduction (tax) or the contributions (SG) factored in using the FV function but because they are happening at different frequencies I'm struggling to work out how to factor them both into the one formula. Any help would be appreciated thanks.

[AliGW]

There are instructions at the top of the page explaining how to attach your sample workbook.

[joeu2004]

[.... deleted by me for lack of interest ....]