Absolute numbers of whole blood donations in 2005, 2010, and 2015. (A) Total whole blood donations by age group in 2005 (blue line), 2010 (red line), and 2015 (green line) per age group. The total numbers strongly decreased in the age groups 18 to 25 years and 36 to 48 years. In addition, the peak age groups of blood donors shifted by 10 years between 2005 and 2015. The inset shows the numbers of first time donors, which decreased between 2010 and 2015 by 45.6%. Arrows correspond to the median age of the donor population in 2005 (39 years), 2010 (41 years), and 2015 (45 years). (B) The rate of blood donations per 1000 subjects per age group showed only minor changes between 2005 and 2015. The substantial increase in blood donations over nearly all age groups between 2005 and 2010 were due to the start of a new blood service, but this effect was transient and no longer present in 2015. Arrows correspond to the median age of the donor population per 1000 inhabitants in 2005 (38 years), 2010 (36 years), and 2015 (39 years). Supplemental Table 2 provides characteristics of the recipient and donor population by type of hospital and type of blood service.