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 counts are plotted on a log scale, so percentage changes are comparable regardless of the size.  For example, the total US citizens killed by terrorism in 1983 was 276, including those killed in the 1983 Beiruit barracks bombing.  That was 46 times the number recorded for 1976.  By comparison, the number killed in the September 11 attacks was less than 11 times this previous maximum.  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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