decis march revis right benefit pursuant articl council regul eec administr commiss european commun social secur migrant worker regard articl regul eec made respons deal question interpret aris regul eec eec decis publish offici journal european commun march render invalid entri forc regul eec eec take account provis regul ground adopt decis essenti ascertain benefit review articl regul eec review institut account period insur resid complet commenc entitl initi benefit countri compet institut situat member state determin right legisl countri qualifi condit satisfi account period insur resid complet commenc entitl initi benefit countri legisl benefit award review provid articl regul eec take form recalcul accord provis articl regul respect legisl qualifi condit satisfi provis articl regul eec amount benefit establish institut concern basi amount benefit person concern entitl period insur resid complet sole legisl administ amount reduc pro rata length period insur resid complet occurr event insur legisl relat total length period complet beforr occurr event legisl member state concern pursuant articl regul eec review benefit dai event occur member state condit commenc entitl satisfi consid dai event occur definit articl regul eec period insur resid defin recogn insur period period treat regard equival period insur resid legisl member state complet consider purpos aggreg institut member state act accord provis articl regul eec decid articl institut pursuant articl regul eec review benefit previous award bound account calcul theoret amount numer denomin fraction repres pro rata refer articl regul eec period insur resid complet commenc entitl initi benefit legisl administ period consider legisl articl institut pursuant articl regul eec review benefit previous award bound account calcul theoret amount denomin fraction repres pro rata refer articl regul eec period insur resid complet commenc entitl initi benefit legisl member state concern period consider legisl articl determin right legisl member state qualifi condit satisfi account calcul theoret amount denomin fraction repres pro rata refer articl regul eec period insur resid complet commenc entitl initi benefit member state member state legisl benefit previous award period consider legisl articl decis publish offici journal european commun enter forc origin member state octob accord treati access april member state chairman administr commiss jantz