DIA -- Rolled Down and Out

The DIA position was rolled down and out:

Date	Description	Total	aXIRR	aROI
2009-01-06	Buy 1000 DIA @ $89.91	-$89,905.60
2009-01-06	Sell 10 DIA Jan 2009 $90 @ $1.96	$1,940.05	121.7%	78.8%
2009-01-08	Buyback 10 DIA Jan 2009 $90 @ $0.69	-$709.95	-40.1%	-49.8%
2009-01-08	Sell 10 DIA Jan 2009 $86 @ $2.41	$2,390.05	-11.4%	-11.6%
2009-01-12	Buyback 10 DIA Jan 2009 $86 @ $1.14	-$1,159.95	-38.5%	-46.5%
2009-01-12	Sell 10 DIA Feb 2009 $85 @ $4.05	$4,030.05	16.4%	14.3%
2009-02-20	Sell at end of period	$84,790.00	14.1%	12.4%

What the aXIRR and aROI percentages mean on each line (each assumes stock price will remain unchanged to the end of the option expiration period):

• On the sale of a call, they state the returns at the point the call was sold.
  
• On the repurchase of the call, they state the returns just prior to the repurchase of the call.
• On the "Sell at end of Period", they state the returns based on the current stock price.
  

So, the effect of the rolled option can be determined by seeing how the aXIRR and aROI rates change between the "Buyback" and subsequent "Sell" line.