It takes time to compute inflation. That's why the reset inflation rate in May and November does not use the values for May and November inflation (it is not yet available when the rate is announced). Conventionally, percentage values are computed as year over year YoY), meaning Nov21 - Nov22 in your example. Also, there are several inflation series available; seasonally adjusted or unadjusted, including or excluding volatile products like food and energy and the like. Details about how to computethe design of inflation indices would be a seperate (complex) question.
HoweverIn any case, what is used to compute inflation for I bonds is this series, found in the section where it reads
Finally, the next grouping of data shows actually CPI figures from 1913 to present.
All Urban Consumers – (CPI-U) 1913-2022*
The computation is like this (forThe computation is like this
For 1st of Nov, the inflation values (not percentage values, but the actual index value) for March to September isare used because it is semi-annual and as mentioned above, the latest values are not available yet: 2968.08/2875.04 =3.24%, because it is rounded to two decimal places).
That is the inflation rate I showed in my other answer.
This answer replicates the calculation of the current value on the website of TreasuryDirect.
This answer explains why the formula
Composite rate = [Fixed rate + (2 x Semiannual inflation rate) + (Fixed rate x Semiannual inflation rate)]
is designed like that.