A pressure measurement can further be described by the type of measurement being performed. There are three types of pressure measurements: absolute, gauge, and differential. Absolute pressure measurement is measured relative to a vacuum (Figure 2).
For example, the median tenure of workers ages 55 to 64 (10.1 years) was more than three times that of workers ages 25 to 34 years (2.8 years). Also, a larger proportion of older workers than younger workers had 10 years or more of tenure.
For most economies, the working-age population is defined as persons aged 15 years and older, although this varies slightly from economy to economy. The ILO standard for the lower age limit is, in fact, 15 years. For many economies, this corresponds directly to societal standards for education and work eligibility.