# NDX: options-positioning snapshot

Canonical: https://halfonadouble.com/stock/NDX
Data through: 2026-10-16 close
Publisher: Half on a Double

| Published field | Value |
| --- | --- |
| Close (USD/share) | 29,187.55 |
| Delta neutral (USD/share) | 29,983.27 |
| Gamma neutral (USD/share) | 30,154.12 |
| Gamma max (USD/share) | 32,128.06 |
| Open interest (contracts) | 169,618 |
| Nearest-expiration max pain (USD/share) | 30,200.00 (2026-10-19) |
| All-expiration max pain (USD/share) | 30,000.00 |
| Net gamma exposure | -8,906,634 |
| Confirmed GEX flip (USD/share) | 30,154.12 |
| Call wall (USD/share) | 31,000.00 |
| Put wall (USD/share) | 28,000.00 |
| Put/call open-interest ratio | 1.44 |
| Options catalyst-intensity score (0–100) | 66.4 |
| Options directional score (-100 to +100) | -37.5 |
| IV rank | 100.0 |
| Front-minus-back IV | 5.4 pp |
| Front 25-delta risk reversal | 9.0 pp |
| Call OI change, 1 session | -11,702 contracts · -14.4% |
| Put OI change, 1 session | -21,448 contracts · -17.6% |
| Call minus put OI growth, 1 session | +3.2 pp |
| Call OI change, 5 sessions | -6,817 contracts · -8.9% |
| Put OI change, 5 sessions | -17,118 contracts · -14.6% |
| Call minus put OI growth, 5 sessions | +5.7 pp |
| Daily call OI change surprise | -2.56σ (250 prior changes) |
| Daily put OI change surprise | -3.52σ (250 prior changes) |
| Daily call-minus-put growth surprise | +0.81σ (250 prior changes) |
| Daily open interest change (contracts) | -33,150 |
| Daily open interest change z-score (prior 252) | -3.26σ (252 prior changes) |
| Gamma max distance from close | +10.1% |
| Delta neutral distance from close | +2.7% |
| Prior-year sessions closer to gamma max | 98.4% of 252 |
| Prior-year sessions closer to delta neutral | 54.4% of 252 |

## Historical gamma-max cross outcomes

| Direction | Horizon | n | Median | Middle 50% | Above zero | Nominal ≥90% median interval | Confidence floor |
| --- | --- | ---: | ---: | ---: | ---: | ---: | ---: |
| above | Day +1 | 30 | -0.2% | -0.5% to +0.3% | 40% | -0.3% to +0.1% | 0.0% |
| above | Day +3 | 30 | +0.3% | -0.8% to +1.4% | 53% | -0.5% to +1.0% | 0.0% |
| above | Day +5 | 30 | +0.0% | -1.0% to +2.6% | 50% | -0.7% to +0.9% | 0.0% |
| above | Day +10 | 30 | +1.1% | -0.6% to +2.9% | 63% | -0.0% to +2.0% | 0.0% |
| below | Day +1 | 30 | +0.3% | -0.3% to +1.2% | 60% | -0.1% to +0.8% | 0.0% |
| below | Day +3 | 30 | +0.4% | -0.6% to +1.5% | 53% | -0.4% to +0.9% | 0.0% |
| below | Day +5 | 30 | +0.6% | -1.7% to +2.5% | 53% | -1.3% to +1.7% | 0.0% |
| below | Day +10 | 30 | +1.5% | -0.4% to +3.6% | 70% | +0.0% to +2.3% | +0.0% |

Returns are close-to-close after the labelled number of subsequent trading sessions. Cohorts require gamma max to be within 10% of the close on both crossing sessions. Historical windows can overlap and are not independent observations, so interval coverage is not guaranteed.

- [Machine-readable snapshot](https://halfonadouble.com/api/v1/tickers/NDX.json)
- [Historical CSV](https://halfonadouble.com/api/v1/history/NDX.csv)
- [Public aggregate analysis](https://halfonadouble.com/api/v1/analysis/NDX.json?date=2026-10-16&public_schema=4)

An em dash means unavailable, not zero. Values use the same display rounding as the HTML page. This is a current snapshot; full history and individual event paths are on the canonical page.

[Definitions and limitations](https://halfonadouble.com/methodology.md).