Insert The Previous Element From A Hierarchy

The mirror of Insert The Next Element From A Hierarchy - adds the element that comes immediately before the current first element in the working list, based on its position in the hierarchy.

Example

1. Element: 2026 - Jan
2. Insert The Previous Element From A Hierarchy

Produces 2025 - Dec, 2026 - Jan - the instruction correctly crosses the year boundary rather than just decrementing a month number, since it's following the hierarchy's actual element order. Chaining the instruction again would add 2025 - Nov ahead of that, and so on - a trailing window ending at the current month, without hardcoding which months those are.