Syntax: XIRR(G, V, D)
G = a guessed value of the result
V = a range containing a series of cash flows
D = a range containing the dates of cash flows in V
XIRR returns the internal rate of return for a series of cash flows (V) with variable intervals (D). V and D must be one-dimensional ranges and have the same size.
XIRR(0.5, B1..B5, A1..A5) = 0.3632
Excel function: N/A