Read? Measure, Measure, Measure (5) As investors, we should be very concern on Rate of Returns on our investment, and Microsoft Excel function XIRR may be the right tool for us to track and monitor our investment performance. How to use XIRR? XIRR(values,dates,guess) Values is a series of cash flows that corresponds to a schedule of payments in dates. The first payment is optional and corresponds to a cost or payment that occurs at the beginning of the investment. If the first value is a cost or payment, it must be a negative value. All succeeding payments are discounted based on a 365-day year. The series of values must contain at least one positive and one negative value. Dates is a schedule of payment dates that corresponds to the cash flow payments. The first payment date indicates the beginning of the schedule of payments. All other dates must be later ......