"Defining poverty as some portions of a normative standard in a country, usually a proportion of median income. Relative poverty lines are usually expressed as being between 40 or 50 percent of median income. In the United States the absolute poverty line was about 44% of median income when first established in 1963, but is now just about 40%. (In the EU a "low income" threshold is defined as below 60 percent of median income)".
Source: Kamerman, S. B. 2000. "Social Policy Glossary". Columbia University School of Social Work. <https://socialwork.columbia.edu/wp-content/uploads/2015/06/SOCIAL-POLICY-GLOSSARY.pdf>. Accessed 14 May 2020.