Here’s an interesting idea on the effect of the financial crisis on blood donations. http://sacstate-communitynews.blogspot.com/2009/03/blood-donations-drop-in-region.html
But as the bad economy has caused a decrease in blood donations, it has also served to lessen the demand.
People who still have their jobs are anxious to take a day off work to donate their blood. Although it might be expected that the unemployed would be more willing to sell their blood, it turns out that they are likely to be upset and stressed, so they do not feel like donating their blood (http://www.economicshelp.org/blog/economics/economics-of-blood-donation/). Moreover, the majority of the blood donations are supported by businesses, of which many have been shut down. These three reasons combined have led to a decrease in the supply of blood.
However, the demand for blood has decreased, ofsetting the decrease in supply:
Botos said Yolo County hospitals have reported a recent and significant drop in elective surgeries and that could account for the decreased demand.