Add documentation about batuzIncomeTaxes

[arraintxo]

There's no schema info about it

[rhejuilna27]

i saw that bizkaia needs submit batuzIncomtaxes.But the structure and instructions provided on the official website are unclear, how should I fill them out.
the official website provided this

this lib's "tbai-sample-self-employed.json" as follows

This confuses me. I don't know what "197330" means. and incomeTaxAmount I don't know if I'm filling in the personal income tax base or tax amount. From the name, it should be the tax amount, but I don't know how this tax amount was generated

[arraintxo]

This is only needed if the worker is self employed and only applicable to Bizkaia's Batuz system.

The epigraph is a number that the workers must set for their invoice lines. The epigraph is a number that self-employed workers must assign to their invoice lines. This number corresponds to the IAE (Impuesto de Actividades Económicas) code for their business activity. A self-employed person may have more than one epigraph associated with different activities, and each invoice line may relate to a different IAE code.

Self-employed individuals are required to apply an income tax withholding ("retention") to their activity. This retention is deducted from the invoice and must be paid by the recipient in their next tax declaration.

This retention amount must be specified for each epigraph. For example, if epigraph 197330 is subject to a 25% withholding rate and the total base amount of the invoice lines associated with this epigraph is is 1600€, the incomeTaxAmount would be 400€.

I hope this explanation makes the concept clearer.

[rhejuilna27]

Can you tell me why the amount is associated with this setting? I see that there are other merchants who are not together. Look at the screenshot he sent me below

The screenshot below is the one I submitted：

Does this setting have any impact？