not open source (and not the above calendar), but similar and useful if you're not on windows: https://docs.google.com/spreadsheets/u/2/d/1m1IWh6Mmli8K20DdH2wb7

not open source (and not the above calendar), but similar and useful if you're not on windows: https://docs.google.com/spreadsheets/u/2/d/1m1IWh6Mmli8K20DdH2wb7glls3dTgJRdCrFY0e1C-Sg/template/preview#gid=742254141 https://docs.google.com/spreadsheets/u/2/d/1m1IWh6Mmli8K20Dd... [+ attribution] Many thanks to Pedro Pablo Fuentes Schuster for this Google Sheets conversion! http://pedrofuent.es/ http://pedrofuent.es/