[Quantlib-users] Seasonality calculations

[Magnus G. <mag...@ho...>]

Dear all,

I am currently using QuantlibXL, the newest version being 1.22, and having some issues with seasonality.
I`ve attempted to replicated the results I get in excel manually. However, there is one variable which I cannot identify the source to.

In MultiplicativePriceSeasonality::seasonalityCorrection, a Rate is passed as an argument which changes several times (for each date that the seasonality adjustment is expected, say monthly, when utilising breakpoints in the code) without me identifying a pattern.
Does anyone know why this rate is added? Is it perhaps an adjustment to remove a trend in the underlying CPI index?

Kind Regards,
Magnus