LIMITED OFFICIAL USE-LAW ENFORCEMENT SENSITIVE//FOR OFFICIAL USE ONLY

U.S. Department of Justice
National Drug Intelligence Center
Monthly Drug Summary: Southwest Border Drug Seizure Statistics Report--March 2010 and Year-to-Date 2010
June 11, 2010

Appendix C. Methodology

Methodology of Data Analysis

(LES//FOUO) NDIC, at the request of the Office of National Drug Control Policy (ONDCP), began to prepare this monthly intelligence product in January 2007 to help policymakers and law enforcement decisionmakers identify key locations through which illicit drugs are smuggled to the United States across the U.S.-Mexico border (Southwest Border). The report provides a monthly summary and YTD analysis of CBP seizure data for the Southwest Border area of the United States. In preparing this report, NDIC analysts review detailed data regarding seizure activity at and between POEs along the Southwest Border. These data are provided to NDIC by CBP at the conclusion of the most current month. The YTD references contained in this report commence January 1 and end March 31 of each year from 2006 through 2010. Detailed CBP data by POE, sector, and area can be found in the Southwest Border Drug Seizure Statistics Supplement (Product No. 2010-R0926-005a).

(LES//FOUO) All statistical data originated from one of two offices within CBP--the Office of Border Patrol (OBP) or the Office of Field Operations (OFO). OBP agents report on illicit drugs seized between POEs, including at fixed and roving checkpoints, within sectors. OFO officials report on illicit drug seizures at POEs. Seizure amounts in sectors include all seizures made in the remote areas between POEs and at fixed and roving checkpoints; the data cannot be further broken down into the quantities seized at specific locations. It is possible that drug shipments seized at checkpoints entered the country at POEs. Interdictions at OBP checkpoints account for a large portion of drugs seized between POEs.

(LES//FOUO) All seizure statistics identified in this report--current as of April 30, 2010--relate to seizures of marijuana, cocaine, methamphetamine, and heroin that involved a land conveyance and occurred in or near the Southwest Border area. For the purposes of this report, all Southwest Border references include Arizona, California, Nevada, New Mexico, Texas, and Oklahoma. Nevada and Oklahoma are included in the Southwest Border area only because the state of Nevada is within CBP's OBP Yuma Sector, and the state of Oklahoma is likewise included in CBP's OBP Marfa Sector. Additionally, northern and central California typically are not considered a part of the Southwest Border area; however, the El Centro and San Diego Sectors include portions of each and are, therefore, given full consideration in this report. Airport and seaport seizure amounts were not considered in this assessment because the conveyances and the drugs being transported could have originated in a country other than Mexico, and the inclusion of such data could inaccurately portray the drug seizure threat along the Southwest Border.

(LES//FOUO) Areas are depicted on the maps using sector boundaries and titles; however, the totals include both OFO POE and OBP sector seizure amounts. The four OFO office territories and seizure amounts as well as the nine OBP sectors and seizure amounts for the Southwest Border are depicted separately on the maps in accordance with CBP's standard operating procedures.

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Methodology of Drug Seizure Status Maps

(U) The Drug Seizure Status maps present a view of overall drug seizure quantities along the Southwest Border. An index score (see formula below) is used to enable a consistent comparison of seizure quantities among the nine areas and over time. An index score is used as a means to evaluate the overall level of drug seizure quantities and is equalized for the four major drugs--cocaine, heroin, marijuana, and methamphetamine. The index score is a composite derived by dividing the monthly seizure amount for an area by the greatest historical seizure amount for the entire Southwest Border and then multiplying the result by a weighting factor. The results for the four drug types are summed together to produce one composite index score. (See text box below.)

(U) Index Score Formula Index Score Formula: i = ∑ w(s/g) i = index score s = seizure amount of the respective drug (cocaine, heroin, marijuana, or methamphetamine) g = greatest historical amount of the respective drug for total Southwest Border in benchmark period from January 2004 through December 2007 w = weighted value (combined weights will total 100) The following example illustrates how the August 2007 index score of 12.18 was calculated for seizure quantities in the Rio Grande Valley Area:   Seizures at POEs in the Rio Grande Valley Area + Seizures in the Rio Grande Valley Sector = Rio Grande Valley Area Total(s) / Greatest Southwest Border Historical Amount (g) = Current Month ÷ Historical Border Maximum x Weighting Factor* (w) = Index (i) Cocaine 125.86 + 388.62 = 514.48 / 2,576.26 = 0.20 x 25 = 4.99 Heroin 15.27 + 0.00 = 15.27 / 68.56 = 0.22 x 25 = 5.57 Marijuana 66.00 + 5,262.00 = 5,328.00 / 113,154.00 = 0.05 x 25 = 1.18 Methamphetamine 5.04 + 0.00 = 5.04 / 286.41 = 0.02 x 25 = 0.44 Final Index Score = 12.18 * Sum equals 100. The index score is visually depicted on the maps by color, which identifies the overall level of drug quantities seized. The index score range for each level is as follows: Very High 15.00 or greater High 10.00-14.99 Moderate 5.00-9.99 Low 1.00-4.99 Very Low Less than 1.00

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