I am dicounting a series of future cash flows at two rates back to 1/25/06 .
The cashflows are quarterly and even once we get to 2018 but the first and
the last payments are different than all the other payments . Because I have
exact dates, to simplify the calculation I used the XNPV fucntion. I checked
my work by recalclulating, discounting quarterly, using the NPV and PV
function in Excel and on my HP. The quarterly discounting gives a very
different answer from the XNPV result. Because the XNPV function discounts
daily, I would have expected the XNPV result to be a lower present value than
under quarterly discounting. My results are below. Can anyone help me get a
comfort level on what the PV is for this series of cash flows?

Many thanks in advance,
Anne

Discount HP 12C
Rate XNPV (below) NPV(Excel) PV (Excel) NPV then PV
16.0% $15,325,146 $13,530,060 $13,514,077 $13,530,060
17.5% $12,662,811 $10,931,861 $10,917,838 $10,931,861
Difference $2,662,335 $2,598,198 $2,596,238 $2,598,198
(NPV is end of period
started at 4/25/06)

16.0% 17.5%
Cash Payment PV at PV at
Flow Date Quarters 1/25/2006 1/25/2006
0 1/25/2006 - - -
2,593,876 1/25/2018 48 394,266 331,670
5,276,303 4/25/2018 49 771,560 646,763
5,276,303 7/25/2018 50 741,964 619,726
5,276,303 10/25/2018 51 713,197 593,540
5,276,303 1/25/2019 52 685,545 568,461
5,276,303 4/25/2019 53 659,532 544,953
5,276,303 7/25/2019 54 634,234 522,172
5,276,303 10/25/2019 55 609,644 500,109
5,276,303 1/25/2020 56 586,007 478,977
5,276,303 4/25/2020 57 563,529 458,954
5,276,303 7/25/2020 58 541,913 439,768
5,276,303 10/25/2020 59 520,902 421,187
5,276,303 1/25/2021 60 500,706 403,390
5,276,303 4/25/2021 61 481,707 386,708
5,276,303 7/25/2021 62 463,229 370,542
5,276,303 10/25/2021 63 445,269 354,886
5,276,303 1/25/2022 64 428,005 339,891
5,276,303 4/25/2022 65 411,765 325,835
5,276,303 7/25/2022 66 395,970 312,214
5,276,303 10/25/2022 67 380,618 299,022
5,276,303 1/25/2023 68 365,861 286,387
5,276,303 4/25/2023 69 351,978 274,544
5,276,303 7/25/2023 70 338,477 263,067
5,276,303 10/25/2023 71 325,354 251,951
5,276,303 1/25/2024 72 312,739 241,306
5,276,303 4/25/2024 73 300,743 231,218
5,276,303 7/25/2024 74 289,207 221,552
5,276,303 10/25/2024 75 277,994 212,191
437,573 1/25/2025 76 22,161 16,854

13,514,077 10,917,838