Milestones

Ten years ago: The nation’s worst oil spill occurred as the supertanker Exxon Valdez ran aground on a reef in Alaska’s Prince William Sound and began leaking 11 million gallons of crude.

Five years ago: President Clinton held a news conference in which he acknowledged he had significantly overstated the loss in his Whitewater land investment and promised to release late 1970s tax returns to answer questions on the land deal.

One year ago: Two students, ages 13 and 11, opened fire outside their school in Jonesboro, Ark., killing four classmates and a teacher.