On Jan 7, 4:53*pm, "Carl LaFong" wrote:
I was referring to a hypothetical 10,000 dollar investment, not to a 10k
filing with the Securities and Exchange Commission. Sorry for the confusing
shorthand.

Of course you were. Silly me! No apology needed -- except mine. Mea
culpa!

This has been a fun exploration. I learned a lot from it, having
taken a lot of things for granted for many years. It will be
interesting to see what holes people poke into my thoughts here.

Errata....

Annual XIRR construction:

12/31/2006 -10000 (initial investment; previous year-end value)
1/1/2007 -100
2/1/2007 -100
3/1/2007 -100
4/1/2007 -100
5/1/2007 -100
6/1/2007 -100
7/1/2007 -100
8/1/2007 -100
9/1/2007 -100
10/1/2007 -100
11/1/2007 -100
12/1/2007 -100
12/31/2007 13,055.39 (year-end value)
17.4488% (annual XIRR)

Quarterly XIRR construction:

12/31/2006 -10,000.00 (initial investment; previous year-end value)
1/1/2007 -100.00
2/1/2007 -100.00
3/1/2007 -100.00
3/31/2007 10,228.62 (quarter-end value)
-0.7000% (quarterly XIRR)
2.2862% (endBalance/startBalance - 1)

3/31/2007 -10,228.62 (previous quarter-end value)
4/1/2007 -100.00
5/1/2007 -100.00
6/1/2007 -100.00
6/30/2007 11,101.95 (quarter-end value)
5.5000% (quarterly XIRR)
8.5381% (endBalance/startBalance - 1)

6/30/2007 -11,101.95
7/1/2007 -100.00
8/1/2007 -100.00
9/1/2007 -100.00
9/30/2007 11,740.86
3.0000%
5.7549%

9/30/2007 -11,740.86
10/1/2007 -100.00
11/1/2007 -100.00
12/1/2007 -100.00
12/31/2007 13,055.39
8.5000%
11.1963%

Product of quarterly XIRRs: 17.0762%

Product of quarterly endBalance/startBalance - 1: 30.5539%
Annual endBalance/startBalance - 1: 30.5539%