• Data on sickness absence over 2008 are based upon the Quarterly survey sickness absence.
• Data on 2006 and 2007 are based on annual surveys and aggregated branch data.
• Sickness absence data over 2004 and 2005 are compiled on the basis of the National survey on sickness absence and aggregated branch data. Figures on 2004 refer to periods to a maximum of one year. Since 2005, data include absence periods longer than one year.
• Figures over the period 1993–2003 are based on the Survey sickness absence private sector. This survey does not cover the sectors public administration and education. These data refer to absence periods of no more than one year.
The differences mentioned above should be taken into account, when sequential periods are compared.