Most people memorize their telephone and cellphone numbers, identity card numbers and many others, but over half of all adult Israelis don't know whether their blood type is O, A, B or AB and + or -, according to a Magen David Adom survey commissioned to mark International Blood Donors Day on Sunday. "I can't say that we were really surprised," said Prof. Eilat Shinar, director of MDA's blood services. "Usually only regular blood donors know, especially if they have a rare blood type or if they are young mothers." The poll was conducted by the Geocartography polling company among 500 adults who constituted a representative sample of the population. Only 48 percent said they knew their blood type. In addition, 19% said they "thought" they knew and 33% said they did not know at all. But 59% of women said they knew their blood type, compared to only 35% of the men. Among adults aged 18 to 34, just 36% said they knew their type, compared to 54.5% of those over 55. The well educated who have an academic degree were more likely to know - 58% compared to 41% of those with a high school education. For some reason, Sharon region residents were much more likely to know their blood type - 64% - compared to 44.7% in the Jerusalem area, 43% in the Tel Aviv area and 45% in the south. Residents of Zichron Ya'acov are the champions in donating blood, with 7% of them saying they gave blood during the past five years. Next were Binyamina, Pardes Hanna, Shlomi, Nahariya, Kiryat Bialik and Shoham with 5%. Only 2% of the populations of Jerusalem, Bnei Brak, Ashdod, Bat Yam, Givat Ada, Kiryat Malachi and Shfaram donate blood, while Lod is at the bottom of MDA's list, with only 1%. MDA director-general Eli Bin said that the blood supply, first-aid and ambulance organization decided to mark International Blood Donors Day with donations in the community. Special honors at a ceremony on Sunday will go to Zichron Ya'acov. Blood donation rates plummeted during the summer months and the holidays, even though the need for blood continued throughout the year, he said. Shinar said MDA needs 30,000 donated pints of blood a year to meet the country's needs. That constitutes less than half of a percent of Israel's population. Every healthy person can donate at least twice a year and save lives.