Silver Book Fact
In 2011, the 15.2 million family and other unpaid caregivers of people with Alzheimer’s disease and other dementias provided an estimated 17.4 billion hours of unpaid care.
Alzheimer's Association. 2012 Alzheimer’s Disease Facts and Figures. Alzheimers Dement. 2012; 8(2): 131-68. http://www.alzheimersanddementia.com/article/S1552-5260(12)00032-5/fulltext