"Consistent with its statutory mission to serve as the United States government's knowledge bank on international terrorism, the National Counterterrorism Center (NCTC) is providing the Department of State with required statistical information to assist in the satisfaction of its reporting requirements under Section 2656f of title 22 of the US Code (USC). This statute requires the State Department to include in its annual report on terrorism 'to the extent practicable, complete statistical information on the number of individuals, including United States citizens and dual nationals, killed, injured, or kidnapped by each terrorist group during the preceding calendar year.' While NCTC keeps statistics on the annual number of incidents of 'terrorism,' its ability to track the specific groups responsible for each incident involving killings, kidnappings, and injuries is significantly limited by the availability of reliable open source information, particularly for events involving small numbers of casualties. Moreover, specific details about victims, damage, perpetrators, and other incident elements are frequently not fully reported in open source information."
National Counterterrorism Center: http://www.nctc.gov/