Private Equity IRR Calc

[lordrummxx1]

Hey All,

Quick question, I'm trying to calculate an ongoing IRR calc for a Private Equity Investment. For every period, I want to have an IRR calc up to that point. I need to somehow bring in the Fair Value of the fund on that date into the last cash flow of the IRR calc, otherwise the Cash In/Cash Out will be understated. See example, with the blue representing the cash flow in the IRR calc:
[TABLE="width: 500"]
<tbody>[TR]
[TD]Date[/TD]
[TD]6/30/2012[/TD]
[TD]9/30/2012[/TD]
[TD]12/31/2012
[/TD]
[/TR]
[TR]
[TD]Contributions[/TD]
[TD](7,000,000)[/TD]
[TD]0[/TD]
[TD](5,000,000)[/TD]
[/TR]
[TR]
[TD]Fair Value[/TD]
[TD]7,500,000[/TD]
[TD]7,600,000[/TD]
[TD]7,800,000[/TD]
[/TR]
[TR]
[TD]Distributions[/TD]
[TD]500,000[/TD]
[TD]500,000[/TD]
[TD]500,000[/TD]
[/TR]
[TR]
[TD]Net[/TD]
[TD](6,500,000)[/TD]
[TD]500,000[/TD]
[TD]3,300,000[/TD]
[/TR]
[TR]
[TD]IRR[/TD]
[TD]10%[/TD]
[TD]9%[/TD]
[TD]10%[/TD]
[/TR]
</tbody>[/TABLE]

I just made up the numbers, but I currently have it set up as summing the contributions with distributions, but I need to include the Fair Value of the fund in the last period for each time period. For example, on 9/30/2012, I would want my IRR formula to show my cash flows as (6,500,000) on 6/30/2012, and 8,100,000 on 9/30/2012.