which ended during the Depression era. Nonetheless, in addition to a significant student population from the Delaware Valley, Penn attracted international students from at least 50 countries and from all 50 states as early as the second decade of the 20th century. Referring to the expansion in students (particularly from the Delaware Valley) due to Servicemen's Readjustment Act of 1944 (commonly known as the G.I. Bill), Penn Trustee Paul Miller remarked about Penn's undergraduate housing situation in the post World War Two era that: "[t]he bricks-and-mortar Capital Campaign of the Sixties...built the facilities that turned Penn from a commuter school to a residential one...." By 1961, 79% of male undergraduates and 57% of female undergraduates lived on campus. Controversies From 1930 to 1966, there were 54 documented Rowbottom riots, a student tradition of rioting which included everything from car smashing to panty raids. After 1966, there were five more instances of "Rowbottoms", the latest occurring in 1980. In 1965, Penn students learned that the university was sponsoring research projects for the United States' chemical and biological weapons program. According to Herman and Rutman, the revelation that "CB Projects Spicerack and Summit were directly connected with U.S. military activities in Southeast Asia", caused students to petition Penn president Gaylord Harnwell to halt the program, citing the project as being "immoral, inhuman, illegal, and unbefitting of an academic institution". Members of the faculty believed that an academic university should not be performing classified research and voted to re-examine the university agency which was responsible for the project on November 4, 1965. In 1983, members of the Animal Liberation Front broke into the Head Injury Clinical Research Laboratory in the School of Medicine and stole research audio and video tapes. The stolen tapes were given to PETA who edited the footage to create a film, Unnecessary Fuss. As a result of media coverage and pressure from animal rights activists, the project was closed down. The school gained notoriety in 1993 for the water buffalo incident in which a student who told a group of mostly black female students to "shut up, you water buffalo" was charged with violating the university's racial harassment policy. In 2022, some asked for the tenure of a University of Pennsylvania law school professor to be revoked after she said the country is "better off with fewer Asians." Educational innovations Penn's educational innovations include the nation's first medical school