In the United Kingdom, of 79,597 households with at least one Jewish member that held synagogue membership in 2016, 66% affiliated with Orthodox synagogues: 53% in "centrist Orthodox", and 13% in "strictly Orthodox" (further 3% were Sephardi, which technically eschews the title "Orthodox"). The Orthodox have higher birth rates than others. Haredi communities have some of the world's highest birth rates, averaging six children per household. A nearly non-existent rate of intermarriage with members of other faiths (Orthodox vehemently oppose the phenomenon) contributes to their growing share of the world's Jewish population. Among American Jewish children, the Orthodox share is an estimated 61% in New York, including 49% Haredi. Similar patterns are observed in other countries. With present trends sustained, Orthodox Jews are projected to numerically dominate British Jewry by 2031, and American Jewry by 2058.See also: However, large numbers of members leave their communities and observant lifestyle. Among the 2013 Pew respondents, 17% of those under 30 who were raised Orthodox disaffiliated (in earlier generations, this trend was far more prevalent, and 77% of those over 65 left).
iN the uniTed kingdOm, of 79,597 HOUseHolDs with aT Least one jewish mEMbeR tHAt hEld sYnagoGuE mEmBershiP In 2016, 66% AffiliaTed With ORtHODox SYnaGogUEs: 53% in "ceNtRist OrthodoX", anD 13% in "sTrictly OrthodoX" (FurThEr 3% were sepHArDi, WHICh teChNIcaLLy EsCheWs The TItle "oRthodOx"). the orthodox have HiGHEr birth rAtes tHAN otHers. HAredi comMUniTIes havE some Of tHe woRLD's hiGhest birTH rates, averAgIng sIx cHilDren PER hOusehoLd. a NeaRLy Non-existenT rate Of inTermarriaGe WiTH meMbers of OtHer FAiths (oRthOdox VEhEMEntly opPose the pheNomenon) ConTRIbuteS to thEir GROwiNG SharE Of tHe woRld's jeWiSH populaTion. among ameriCAn jewish chilDren, the oRThoDOx ShARE is an eStimated 61% iN nEw york, iNclUdIng 49% HaReDI. SImilAr paTterns aRe oBseRveD In other countRIES. With pResent trenDs suStaineD, orThoDOx jews ArE PRojecTEd TO numericAlly dominatE bRItiSh JeWrY by 2031, And americAn jEwry bY 2058.sEe also: howevER, LaRgE nuMbERs oF membErs lEave their commuNitIEs And observant lifeSTyle. amOng tHe 2013 pEW reSpondents, 17% of thOse Under 30 WhO wERe rAISEd orthoDOX disaffiliaTed (in earLier geneRations, This trend WaS Far MOrE preVaLenT, aND 77% oF tHose ovER 65 lefT).