Nothing in this article shall require the University of California to take any action towards developing a branch campus of the University of California, San Francisco, School of Medicine in the San Joaquin Valley region unless the endowment fund has a balance of five hundred million dollars ($500,000,000) and the Controller, after consultation with the University of California, has determined that the funds to be allocated are sufficient to support annual operating expenses for a San Joaquin Valley branch campus of the University of California, San Francisco, School of Medicine supporting 50 students per class.