When we write vectors as matrices, we tend to write an $n$-dimensional vector vector as $n \times 1$ column matrix. We emphasize that the gradient vector is defined only for scalar-valued functions. For vector valued functions, we will stick with viewing the derivative as a matrix.
Gloomy Addiction Relapse Statistics. Drug and alcohol rehab statistics show that the percentage of people who will relapse after a period recovery ranges from 50% to 90%. This is a frightening statistic and it is often used as justification for those who wish to carry on with their addiction.
Prescription drugs now account for about 10 percent of seniorsâ health costs â and will likely rise to 13.3 percent in 2010, the report said. Older Americans account for only 13 percent of the nationâs population but pay 42 cents of every dollar spent on prescription drugs, it said.