In general, some time elapses between the actual date of death and the moment when this data reaches CBS. Death records are collected weekly on Thursdays. Usually, mortality data collected on Thursday include slightly over 80 percent of all deaths over the previous week. Therefore, it provides an indication of the number of deaths that can be expected for that week.Over the past several weeks, death records have been received earlier than usual (on average, the number of records that was received after one week covered 83 percent of the total). The estimate for week 51 is based on the assumption that for this week as well, 83 percent has been received. As the percentage is uncertain, the actual number of deaths in week 51 may be higher or lower as a result.