SURVEYDESIGNANDMETHODS Throughoutthisreport,weusetheterm“in-network”torefertoservicesreceivedfromapreferredprovider. Familycoverageis definedashealthcoverageforafamilyoffour. Thesurveyasksfirmswhatpercentageoftheiremployeesearnlessthanaspecifiedamountinordertoidentifytheportionofa firm’sworkforcethathasrelativelylowwages. Thisyear,theincomethresholdis$24,000peryearforlower-wageworkersand $60,000forhigher-wageworkers. Thesethresholdsarebasedonthe25thand75thpercentileofworkers’earningsasreported 9 bytheBureauofLaborStatisticsusingdatafromtheOccupationalEmploymentStatistics(OES)(2016). Thecutoffswere inflation-adjustedandroundedtothenearestthousand. Priorto2013,wagecutoffswerecalculatedusingthenow-eliminated NationalCompensationSurvey. ROUNDINGANDIMPUTATION Somefiguresinthereportdonotsumtototalsduetorounding. Inafewcases,numbersfromdistributionfiguresmay notaddtothenumbersreferencedinthetextduetorounding. Althoughoveralltotalsandtotalsforsizeandindustryare statistically valid, some breakdowns may not be available due to limited sample sizes or a high relative standard error. Where theunweightedsamplesizeisfewerthan30observations,figuresincludethenotation“NSD”(NotSufficientData). Estimates withhighrelativestandarderrorsarereviewedandinsomecasesnotpublished. Manybreakoutsbysubsetsmayhavea large standarderror, meaningthatevenlargedifferencesarenotstatisticallydifferent. Statisticsamongsmallfirmsandthose weightedbythenumberoffirmstendtohavemorevariability. Tocontrolforitemnonresponsebias,Kaiser/HRETimputesvaluesthataremissingformostvariablesinthesurvey. Onaverage, 5%ofobservationsareimputed. Allvariablesareimputedfollowingahotdeckapproach. Thehotdeckapproachreplaces missinginformationwithobservedvaluesfromafirmsimilarinsizeandindustrytothefirmforwhichdataaremissing. In 2017,therewereelevenvariableswheretheimputationrateexceeded20%;mostofthesecaseswereforindividualplanlevel 9 GeneralinformationontheOEScanbefoundathttp://www.bls.gov/oes/oes_emp.htm#scope. AcomparisonbetweentheOESandtheNCSisavailableat https://www.bls.gov/opub/mlr/2013/article/lettau-zamora.htm The Kaiser Family Foundation and Health Research & Educational Trust / Page 20