The collection of data for this report would have not been possible without the effort of Lorena Andrea Morantes and Giorgina Medina, nor without the assistance of professor Mabel Calderín. We would also like to thank everybody who took some time to answer our questions, especially Raisa Urribarrí and Andrés Cañizález, whose expertise was of great value in some of the most complex parts of this work.