I am getting a really weird XIRR result for the following series of cash flows:

4/27/07 $43,750.00
9/11/07 $(437,500.00)
10/11/07 $(433,008.33)
11/11/07 $(428,217.22)
12/11/07 $(424,025.00)
1/11/08 $(418,934.44)
2/11/08 $(414,293.06)
3/11/08 $(411,448.33)
4/11/08 $(405,010.28)
5/11/08 $(401,566.67)
6/11/08 $(395,727.50)
7/11/08 $(392,583.33)
8/11/08 $(386,444.72)
9/11/08 $(381,803.33)
10/11/08 $(379,108.33)
11/11/08 $(372,520.56)
12/11/08 $(370,125.00)
1/11/09 $74,262.22
2/11/09 $74,262.22
3/11/09 $67,075.56
4/11/09 $74,262.22
5/11/09 $71,866.67
6/11/09 $74,262.22
7/11/09 $71,866.67
8/11/09 $74,262.22
9/11/09 $74,262.22
10/11/09 $71,866.67
11/11/09 $74,262.22
12/11/09 $7,071,866.67

TOTAL CF $1,465,811.67
XIRR = 305,076.9%

This can't be right, can it? It's only net ~$1.5mm...that doesn't strike me
as a 300,000% return. Help?