The Administration of the State of Zurich in Switzerland still uses the proprietary xls, doc etc. Formats of the MS Office Suite. That’s why each an every worker of the state of Zurich has to write its timetable into a table of such a proprietary file. Today while transfoming my timetable.xls file into a ODF (Open Document Format) file I coincidentally found out that the timetable with its calculations and algorithms still works perfect in Openoffice. And it also does in ISO certified ODF Format we could economise 70% of our storage Servers, that could be used for example for another Free Software project in Malawi.