Model a Portfolio of I Bonds
This is a calculator to model a portfolio of Series I Savings Bonds ("I Bonds") over time.
Instructions for Modeling an I Bond Portfolio
- Add an I Bond holding to this form.
- Specify the date of purchase in the
Date
field. - Specify the value of purchase in the
Value
field.
- Specify the date of purchase in the
- If you have more than one holding, press
Add row
to add another row for your holding. Repeat the previous steps for that holding. - When you are done, press
Compute
.
The computation engine will generate both a graphical and tabular presentation of the holding's value and performance over time.
Additional Uses for this Tool
ibondcalc.info
can backtest portfolios of
I Bond holdings.
ibondcalc.info
also has a database of historical fixed interest rates
as well as their attendant inflation rates according to the
United
States Bureau of Labor Statistics for each bond issuance.
For example, it can model
$1,000 of I Bonds purchased in September 1998 to today.
If You are Lost
If you are brand new to I Bonds and don't know what they are, consult the Bogleheads' resources. They have a wealth of information, including an article on I Bonds. You may find I Bonds useful for the following purposes (not exhaustive):
- Building an emergency fund over multiple years
- Extending tax-advantaged preservation of wealth