How many vice presidents have had to replace presidents who died in office over the course of American history?

There have been eight vice presidents who had to step up to the role of president because of death. 1. William Harrison died which resulted in John Tyler becoming president. 2. Zachary Taylor died which resulted in Millard Fillmore becoming president. 3. Abraham Lincoln died which resulted in Andrew Johnson becoming president. 4. James Garfield died which resulted in Chester Arthur becoming president. 5. William McKinley died which resulted in Theodore Roosevelt becoming president. 6. Warren Harding died which resulted in Calvin Coolidge becoming president. 7. Franklin Roosevelt died which resulted in Harry Truman becoming a president. 8. John F. Kennedy died which resulted in Lyndon Johnson becoming president.

It should be at the center of any map going vertically: the prime meridian, as it passes through greenwich,  england, is considered 0 degrees longitude