Historical clue formulations

• Lengths for rulers — 2020-08-16
• Rules as a monarch — 2018-01-23
• 1910-36 for George V, and 1936-52 for George VI — 2010-08-03
• Is a monarch — 2003-10-21
• Acts as king — 1997-10-27
• Rules — 1994-12-25