From Wikipedia: Decline of Jews in Europe since 1945
The findings of a comprehensive study undertaken by the Institute for Jewish Policy in London were published at the beginning of this week showing that the total number of Jews in all of Europe, including England, Turkey and Russia, is at its lowest in the past millennium.
The study shows that today there are only 1.3 million people in Europe who define themselves as Jews. This is so low as to compare with the estimate of the famous traveler Binyamin of Toledo in the year 1170 C.E.
The latest study indicates that since 1970, Europe in its entirety has lost about sixty percent of its Jewish population. In 1970, all of Europe including Russia, numbered some 3.2 million Jews.
From this figure, the study shows, about 1.5 million Jews left the continent after the fall of the Iron Curtain. Apart from emigration, there is an outward flow of Jews from other Western countries like France, for example.
France boasted some 530,000 Jews in 1970 while today there are only 449,000 Jews after the emigration to Israel numbering 51,455 and many others went off to Canada,
The depleted state of Jewish communities does not only apply only to France. The study showed that of the 118,000 Jews now in Germany, 40% are above 65 and only 10% are under 15. In other words, the Jewish German population is aging and disappearing without any projected increase. In Turkey there were 39,000 Jews in 1970 but today there are only 14,000.
From Wikipedia: Some of the expulsions over the centuries
It is interesting to note that this study, relying upon a census of the European Community from 2018 and an extensive study of the communities on the continent, shows a more pessimistic picture than what other organizations present. The European Jewish Congress reports some 1,929,650 Jews, while according to the World Jewish Congress, the European continent has only 1,438,000 Jews.
Assimilation is rampant. 70 percent of Polish Jews marry out. In Hungary, Holland, Denmark and Sweden the figure is 50 percent.
The study says there are only 70,000 Israelis in Europe today.
The study concludes: "In most countries the number of Jews will continue to decline due to assimilation and low fertility. Soon Canada will replace France as the third largest Jewish community after Israel and the US. Eventually all that will remain are chareidi communities."