You can ask taxes from your natives and colonists.

  • Tab: Switch between colonists and natives
  • +, Right: Increase taxes (with prefix: by that amount)
  • -, Left: Decrease taxes (with prefix: by that amount)
  • ShiftRight: Pick lowest tax rate that gives a higher income (useful on small outposts)
  • ShiftLeft: Pick highest tax rate that gives a lower income
  • CtrlRight: Set tax rate 100%
  • CtrlLeft: Set tax rate 0%
  • Space: Auto tax colonists and natives
  • Shift+Space: Auto tax only current area (colonists or natives)
  • U, Backspace: Undo current area
  • R: Toggle whether the population prediction displays absolute values (default), absolute or relative (percentage) per-turn change. With Shift, toggles between absolute and relative change only.
  • W: Change number of hissers or terraformers for prediction ("how would growth change if I had a heater here?")
  • =, %: (with prefix) Set tax rate to specified value

The Auto Tax function implements "safe-taxing": it will aim at making the happiness 100% within 5..10 turns. If several tax rates yield the same income, it will use the lowest of them for greater population growth. This taxation algorithm is safe because it will not cause riots, not even if you lose a turn. However, other taxation algorithms are known which can yield higher income in many situations (e.g. "growth-taxing").

Reference

Keys:
T from planet screen