Milestones

Ten years ago: Two dozen countries signed the Montreal Protocol, a treaty designed to save the Earth’s ozone layer by calling for reduced emissions of harmful chemicals by the year 2000.

Five years ago: A proposed debate between President Bush and Democrat Bill Clinton was canceled after the Bush campaign’s refusal to negotiate with a bipartisan commission.

One year ago: President Clinton claimed the endorsement of the nation’s largest police organization, the Fraternal Order of Police, in his bid for re-election. Space shuttle Atlantis blasted off more than six weeks late on a mission to pick up NASA astronaut Shannon Lucid from the Russian space station Mir.