Historical clue formulations

• Slice of the economy — 2025-08-17
• Pie chart piece — 2025-04-21
• Slice of pie, mathematically — 2023-11-18
• Private or public division — 2023-02-04
• Any slice of pizza, geometrically — 2021-10-24
• Division of the economy — 2020-08-18
• Pie chart part — 2006-06-18
• Pie chart piece — 2004-11-23
• Pie chart part — 2001-11-26
• Zone — 1999-11-20
• Combat zone — 1999-10-03
• Quadrant, say — 1998-08-07
• Pie graph piece — 1995-10-17
• Pie slice, in geometry — 1995-01-10
• Zone — 1994-11-07