You want XIRR. Just feed XIRR the dates and the cash flows, and it will
calculate the return for you. Remember, to calculate rate of return, all you
need are the cash flows (money in and money out). Intermediate values of the
investment are immaterial.

If you are trying to calculate the return on an existing investment, you
need to assume you sold it on the last day of the period. IE, enter the
date, and the value of the investment as a negative number.

If you need any more help, post back with an example of your data.

Regards,
Fred.

"vg" wrote in message
...
I have two columns: date and value of an investment on that date.
I want to select a date and compute the rate of return on the investment
for
the prior year leading up to the selected date. Is there a possible for
this?