Ohm. Because of that surface resistivity and the surface resistance are often mixed up. In order to differentiate between the two, surface resistiv-ity is often expressed also in Ohm/square (Î©/sq.) which is not a valid unit from the dimensional anal-ysis point of view. 2 Surface resistivity and surface resistance 2.1 Current density and surface cur-
The median age of the world's population was estimated to be 30.1 years in 2016, with the male median age estimated to be 29.4 years and female, 30.9 years.
Age distribution > Population aged 15-24 > Percent: Percentage of total population aged 15-24. Age structure > 0-14 years: The distribution of the population according to age. Information is included by sex and age group (0-14 years, 15-64 years, 65 years and over). The age structure of a population affects a nation's key socioeconomic issues.