Characteristics that reflect the present situation of employees but can be presumed not to have changed much over their working life (such as being a blue-collar worker or having a university degree) are put in the second category.
exploredata-ZA3700_VarV233 exploredata-ZA3700_VarV211 exploredata-ZA3700_VarV187 exploredata-ZA3700_VarV548