Task: Question Answering
Input (English): Passage: From the 1960s to the 1980s historians still considered 100,000 a reasonable estimate of the Jews killed and, according to Edward Flannery, many considered it "a minimum". Max Dimont in Jews, God, and History, first published in 1962, writes "Perhaps as many as 100,000 Jews perished in the decade of this revolution."  Edward Flannery, writing in The Anguish of the Jews: Twenty-Three Centuries of Antisemitism, first published in 1965, also gives figures of 100,000 to 500,000, stating "Many historians consider the second figure exaggerated and the first a minimum". Martin Gilbert in his Jewish History Atlas published in 1976 states "Over 100,000 Jews were killed; many more were tortured or ill-treated, others fled ..." Many other sources of the time give similar figures. Although many modern sources still give estimates of Jews killed in the uprising at 100,000 or more, others put the numbers killed at between 40,000 and 100,000, and recent academic studies have argued fatalities were even lower. A 2003 study by Israeli demographer Shaul Stampfer of Hebrew University dedicated solely to the issue of Jewish casualties in the uprising concludes that 18,000-20,000 Jews were killed of a total population of 40,000. Paul Robert Magocsi states that Jewish chroniclers of the 17th century "provide invariably inflated figures with respect to the loss of life among the Jewish population of Ukraine. The numbers range from 60,000-80,000  to 100,000 , but that "he Israeli scholars Shmuel Ettinger and Bernard D. Weinryb speak instead of the 'annihilation of tens of thousands of Jewish lives', and the Ukrainian-American historian Jarowlaw Pelenski narrows the number of Jewish deaths to between 6,000 and 14,000". Orest Subtelny concludes:. 
Question: According to Shaul Stampfer how many percentage of the total Jewish population was killed? 
Answer type: Number 
Output (English): 50.