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.
It was the primary payer for an estimated 15.3 million inpatient stays in 2011, representing 47.2 percent ($182.7 billion) of total aggregate inpatient hospital costs in the United States. Medicare serves a large population of elderly and disabled individuals.