Mood controls stress: every in-game minute a settler's stress changes by mood x -0.03, so happy settlers calm down and unhappy ones build stress until a mental breakdown at 100. Set a mood and the chart shows where stress is headed - "if the mood stays like this" (real settlers' moods drift as buffs wear off and needs change).
0
Treatment expectation is applied automatically from the unit level and management difficulty. Add any mood sources the settler currently has (food, sleep, room quality, needs, combat, and so on); each one adds its value to the net mood.
20
Relaxed (below 20)Settled (20 to 40)Stressed (40 to 80)Severe (80+), breakdown at 100
Stress at checkpoints
The mood bands (Very Unhappy to Very Happy) and stress bands come straight from GameSystemTable; see the Mood and Stress page for every mood source and the standing modifiers in full.