People in hiding (in numbers)
An estimated number of over 350,000 people went into hiding for shorter or longer periods of time during the occupation. About 25,000 Jews went into hiding. About a third of them were later arrested. (J.C.H. Blom, Crisis, bezetting en herstel; Tien studies over Nederland 1930-1950 (‘Crisis, Occupation, and Recovery; Ten Studies about the Netherlands 1930-1950’, Rotterdam/The Hague 1989, pp. 77 and 89).