Zimmerman's challenge gets no cigar. The 100,000 annual Jewish emigrants figure post-1933 originates directly from the [pro-Zionist] Universal Jewish Encyclopedia (Vol. 7, 1942, pp. 555-556):
In the period between 1925 and 1939, an average of 100,000 Jewish men, women and children emigrated from the area of Jewish misery in Europe each year.
The "area of Jewish misery"
was overwhelmingly Poland -- with its ~3 million Jews, pauperization, and state antisemitism -- plus Romania and the Baltics. The same entry explains that the 1924 U.S. quota law forced HICEM (HIAS-ICA) to open offices in thirty-two countries, precisely to handle this large-scale outflow. Official Polish tallies (109,716 legal Jewish departures 1931–1937) only record
registered (legal) exits; they omit tourist/student visas, exit-tax evasion, and clandestine routes repeatedly noted in HICEM and Joint Distribution Committee reports (per Sanning).
The figure is
further corroborated by the Institute for Contemporary History (IfZ; Munich) itself in 1958:
In the years following 1933 about 100,000 Jews left Poland every year...
Subtracting the well-documented ~427,000 German/Austrian/Czech emigrants (1933–early 1940) from the 1.5 million total (15 years x 100k, for 1925-1939) leaves roughly one million from Eastern Europe, with Poland supplying by far the largest share. Benz and Golczewski (in the anthology commissioned to refute Sanning) ignore this entirely, instead extrapolating the 1931 census at general Polish growth rates -- while conceding their Polish figures "are not certain."
Even if halved, this pre-war emigration alone reduces the 1939 Polish baseline by hundreds of thousands. Add the ~750,000 Polish Jews who fled east in September 1939 (most absorbed and often deported by the Soviets) plus the ~1 million unregistered post-war departures, and the demographic "hole" shrinks dramatically without requiring millions killed by Germans. The orthodox narrative persists only by dismissing its own Zionist sources when they contradict the desired total.