calculate a tax payable in modules

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Note added at 16 minutos (2019-03-13 05:26:20 GMT)
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tax determination according to the modules calculation procedure

It would be useful to have the sentence before this to be sure of the subject but I am assuming it is self-employed workers whose tax can be calculated in two ways, either based on actual profits (estimacion directa) or estimated profits (estimacion objetiva).

IRPF for freelancers and the self-employed can be calculated in two ways:

Estimación Directa, which calculates tax based on your own profits;
Estimación Objetiva, which compares your profits to the standard profits in your sector to calculate a tax payable in modules (this is the less common option). https://www.expatica.com/es/finance/taxes/freelance-taxes-47...

Alivio de 365 días para los autónomos que cotizan por módulos
http://www.autonomos-ciae.es/2018/01/alivio-de-365-dias-para...

Explanation