against middle-class housewives who participated in the real estate market with the use of the pejorative term bok-buin (). Competition for the lottery was intensified by the fact that lottery entrants typically entered the names of other family members and because winners could resell their tickets at full market value, resulting in high levels of speculative investment into the region. By 1985, 89 percent of Gangnam's residents had moved within the last five years, in comparison to 30 percent for the rest of Seoul. Before the 1970s, most prestigious schools in Seoul were located north of the river. As part of the development program in Gangnam, the government provided construction and land subsidies, as well as tax exemptions to schools that moved south of the river, hoping to attract parents to move for their children's educations. As well, the Park government passed the High School Equalization Policy which ended rankings and entrance exams for elite high schools, encouraging these schools to move to Gangnam to regain their reputations. In 1975, Seoul National University relocated from Gangbuk to Gangnam and in 1976, Kyunggi High School, the highest ranked high school in Seoul moved as well. During the following years, a number of elite high schools would move to the Gangnam area, giving the region its reputation as an educational mecca. The migration of these schools to south of the river have been described as the primary reason behind Gangnam's current affluent status. In 1995, the Supreme Court of Korea, the Supreme Prosecutor's Office, and the National Intelligence Service moved to Gangnam from their previous locations north of the river. Economy Wealth is highly concentrated in Gangnam, with the Gangnam and Seocho districts having the greatest proportion of high-income households in Seoul. More than half of all lawyers, doctors, entrepreneurs, financial managers, and civil servants in South Korea live in Gangnam. Gangnam hosts many startup companies and some of the largest South Korean technology companies, particularly along the Teheran Valley. A number of chaebols are headquartered in Gangnam, including the Hyundai Motor Group, the Samsung Group, the GS Group, and the Lotte Corporation. In addition, the LG Corporation and the KB Financial Group are headquartered in the Yeongdeungpo District, on the western part of the region south of the Han River. In 2010, the Gangnam, Seocho, and Songpa districts accounted for ten percent of the total land value of South Korea. The