Where the Fibonacci ratios actually come from
Start with the famous sequence: each term is the sum of the two before it — 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, and so on. The trading ratios do not come from the numbers themselves. They come from what happens when you divide neighboring terms: as the sequence grows, the ratio of one term to the one before it converges on 1.618, the golden ratio. Every other level on a grid is a simple transformation of that one number.
The derivations
| Ratio | Derivation | Role on the grid |
|---|---|---|
| 0.618 | 1 ÷ 1.618 (a term divided by the next one) | The primary retracement |
| 0.382 | 1 − 0.618, and also 0.618² | The shallow retracement |
| 0.500 | Not a Fibonacci ratio at all — the halfway point | Watched because everyone watches it |
| 0.786 | √0.618 | The deep retracement |
| 1.272 | √1.618 | The first extension |
| 1.618 | The golden ratio itself | The primary extension |
| 2.618 | 1.618² | The far extension |
Two things are worth noticing. The .50 level earns its keep through crowd attention, not mathematics — and honest tools say so. And the whole family reduces to one constant transformed by squares and square roots, which is why the levels relate to each other so cleanly across swings of different sizes.
Why any of this matters
Not because markets obey geometry. The practical case is humbler: these ratios give thousands of traders the same measured reference points on the same swings, and heavily watched references become partly self-fulfilling. FibSetups treats them exactly that way — as measurement, not magic. The evidence for any particular level comes from confluence, not from the ratio alone.