Discussion

• Author: Singleton, Nicola; Kalamara, Eleni; Noor, André
• Pages: 37-43

TECHNICALREPORTIEstimatingthesizeofthemainillicitretaildrugmarketsinEurope:anupdate

37

7Discussion

7.1Limitationsandvalidityoftheestimates

Estimatesofthesizeoftheretailmarketforillicitdrugscancontributetoourunderstandingofthedrug

situation,bothintermsofsupplyanddemand,andarevaluabledespitethemanylimitationsintheestimation

processillustratedabove.However,theyareonlyasmallpartoftheoverallpicture.Forexample,theyprovide

anestimateoftheoverallamountspentondrugsbythosewhousethem,butnothingabouttheprofitand

lossesatdifferentstagesofthesupplychain,whoisinvolved,howtheyoperate,whobenefitsmost,etc.As

withlegalretailmarkets,theoverallvalueofthemarketisaffectedbyarangeoffactors,notjustbyhowmany

peopleconsumetheproductandhowmuchtheyconsumebutalsobychangesinprice.Soareductioninthe

retailmarketvaluemight,forexample,betheresultofadecreaseintheamountsconsumedwhileprice

remainsconstantoradecreaseinthepriceoftheproductwithconsumptionremainingstable.

Nevertheless,theycanprovidevaluableinsights,suchastherelativeimportanceofthemarketsfordifferent

drugsandofusebydifferentsubgroupswithinthese,andundertakingtheseestimatesleadstoimprovements

inthedataandmethodsappliedandthedevelopmentofexpertise,andthetargetingofobviousdata

anomaliesandgaps.Theexercisebringsintofocustheareasthatrequireimprovementandsuggestsfuture

developments.

Theintentionoftheprogrammeofworkdescribedinthisreportistodevelopamethodofestimatingmarket

sizethatcanberepeatedregularly,withchangesorimprovementsinmethodanddatadocumented,and

buildsonthedatacollectedbyallEUcountriesinascomparableawayaspossible.Theprimaryaiminitially

hasbeentoprovideanoverallEUestimatecoveringallofthemaindrugsusedintheEuropeanUnion.The

assumptionsandimputationsmadeinordertoobtainfiguresforallcountries,andissuesonthecomparability

oftheunderlyingdata,havepromptedusnottoprovidespecificcountrylevelestimates.Asimprovementsare

madeinthemethodanddatathismaychange.

ThehugediversitybetweencountriesintheEuropeanUnion,intermsofthecharacteristicsofthedrug

markets,theavailabilityofdata,thepopulationsize,theculturesandadministrativesystems,poses

considerablechallengestoproducingretailmarketsizeestimates,anditisclearthatthelimitationsresultin

anestimateofthetotalmarketsizethatislikelytobeaconsiderableunderestimate.Itshouldalsobe

recognisedthatintheshorttomediumterm,improvementsinmethodanddataavailabilitywillinfluencethe

results,makingitdifficulttoquantifytrendscurrently.

Recentexamplesofinnovativestudiesinthisfieldincludelocalsmallerareastudiessuchasthatundertaken

byZobeletal.(2017,2018),inLausanne,Switzerlandinwhichawiderangeofdatasourcesincluding

wastewateranalysisandseizuresdataareconsideredalongsidesurveydataaninterviewswithpoliceand

userstoproduceanestimateofthelocalmarketsizeforheroin,cocaineandotherstimulants.Caulkinsetal.

(2019)takeadvantageofthefactthatlegalcannabismarketsalesdataarenowbecomingavailableinsome

jurisdictionstolookattheextenttowhichwebandgeneralpopulationsurveydataoncannabismatchlegal

salesdatainWashingtonState.Suchstudiesmayprovidevaluableinsightsthatmayimprovemarketsize

estimationprocessesinthefuture.

Keyareasofconcernaresummarisedbelow,theseincludesomemoredetailedconsiderationofpossibleways

ofaddressingtheseinthefutureandinsomecasesconsiderationoftheirpossibleimpact.

Howwelldotheestimatesrepresentthesituationin2017?

Thefinalmarketsizeestimatesarebasedondatafromdifferentyears,rangingfrom2008to2017,sotheywill

notaccuratelyreflecttheactualsituationin2017andtheremayhavebeenchangesovertimethathavenot