The number of assaults against Border Patrol agents has been increasing along the U.S.-Mexican border, but in the San Diego area there has been a steady decline in such incidents for the last three years, newly released statistics showed. In fiscal 1988, officials reported 85 assaults against patrol agents, compared to 99 assaults in fiscal 1987 and 128 in fiscal 1986. But, officials say, that does not necessarily mean that the level of violence is down in San Diego, which has the largest patrol contingent in the nation. Officials also track “armed encounters,” in which an agent finds a weapon on a suspect’s person or in his vehicle but no assault occurs. In fiscal 1988, patrol agents in San Diego registered 108 such armed encounters, continuing an upward trend. In fiscal 1987 officials counted 70 encounters of this type and in fiscal 1986 the number was only 49.