Mortality rate
Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time. Mortality rate is typically expressed in units of deaths per 1,000 individuals per year; thus, a mortality rate of 9.5 (out of 1,000) in a population of 1,000 would mean 9.5 deaths per year in that entire population, or 0.95% out of the total. It is distinct from the so-called "morbidity rate" (a vague term sometimes used to refer to either the prevalence or incidence of a disease), and also from the incidence rate (the number of newly appearing cases of the disease per unit of time).
Related measures of mortality
Other specific measures of mortality include:
Crude death rate – the total number of deaths per year per 1,000 people. As of 2014 the crude death rate for the whole world is 7.89 per 1,000 (down from 8.37 per 1,000 in 2009) according to the current CIA World Factbook. Note that the crude death rate can be misleading. The crude death rate depends on the age (and gender) specific mortality rates and the age (and gender) distribution of the population. The number of deaths per 1,000 people can be higher in developed nations than in less-developed countries, despite a higher life expectancy in developed countries due to better standards of health. This happens because developed countries typically have a much higher proportion of older people, due to both lower birth rates and lower mortality rates. A more complete picture of mortality is given by a life table, which shows the mortality rate separately for each age. A life table is necessary to give a good estimate of life expectancy.