Spanish to English Bus/Financial Finance (general)

Having trouble finding the right word in English as this is one of three types of withholding taxes in the Peruvian tax system:

https://www.imf.org/external/pubs/ft/scr/2015/cr15134.pdf
A complex system of withholdings, specific to Peru, exists since 2002. The GST systems have helped to
improve GST tax collection: in 2002, the withholding system as a whole represented only 5.3 percent of net
VAT proceeds, but in 2014, that figure exceeded 28 percent. These withholding schemes collect about
4 percent of GDP. However, this set-up has also increased compliance costs and generated certain
administrative inequities.
There are three different withholding schemes in place. They aim to improve compliance and
concentrate revenue collection with large taxpayers: (i) detracciones; (ii) percepciones; and (iii) retenciones.
Together, the system is even more complex (includes more than 10 tax rates):
 Retenciones. This regime forces certain designated companies (large and some public institutions)
to act as withholding agents for the SUNAT, retaining part of the GST that their suppliers were supposed to
pay.
 Detracciones. They are withholdings of GST by large taxpayers on behalf of other taxpayers in the
GST chain to ensure compliance. The system of detracciones was widened in 2012 to incorporate other
services subject to the GST, exempted goods, public entertainment and non-metallic mining. In 2013, the
system was simplified by reducing the number of rates from 13 to 5. The system generates a large number
of GST refunds. The main drawback of the scheme is complexity (e.g., payments are fractioned; the rates and
timing of payment vary by product; returns are delayed). Furthermore, in cases of wood, sugar, alcohol and
rice, the payment has to be made even when these products are not later sold.
 Percepciones. It is a mechanism by which the perception agent charges in advance a fraction of the
GST that his/her customers will generate at a later stage in operations related to the GST. It is usually
charged on purchases by large taxpayers, mainly, of petroleum based liquid fuels and imports.