Terrorism deaths in the US 1970-2020, summarizing " START (National Consortium for the Study of Terrorism and Responses to Terrorism). (2022). Global Terrorism Database, 1970 - 2020. The plotting symbols / letters code for the organization that primarily collected the data during those years:  p = Pinkerton Global Intelligence Service (PGIS).  c = The Center for Terrorism and Intelligence Studies (CETIS). i = The Institute for the Study of Violent Groups (ISVG). s = The National Consortium for the Study of Terrorism and Responses to Terrorism (START).  The data are available with “terrorism”, in Ecdat: Data Sets for   Econometrics[1] (in en), (Please provide a date or year), Wikidata Q114631237.
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