Public holidays vary tremendously from village to village, city to city, canton to canton. So it's no wonder that most sources contain ambiguities or errors.
The spreadsheet is an attempt to consolidate the various sources, e.g.:
- https://de.wikipedia.org/wiki/Feiertage_in_der_Schweiz
- feiertagskalender.ch
- https://so.ch/fileadmin/internet/administrator/dokumente/Gesetzliche_Feiertage.pdf
- Official publication of public holidays of each cantonal website