Data ultima modifica: 18 giugno 2020 Indagine 2020 (PDF, 434.6 Kb) Indagine 2019 (PDF, 473.9 Kb) Indagine 2018 (PDF, 443.6 Kb) Indagine 2017 (PDF, 359.7 Kb) Indagine 2016 (PDF, 413.5 Kb) Indagine 2015 (PDF, 473.4 Kb)