NAS100 vs SPX500 volatility
We compared Dukascopy index-CFD bid feeds on identical qualifying UTC dates and blocks. Percentage normalization, source-gap accounting, and a closed-window label keep the result from confusing points, missing history, or market closure with volatility.
The measured answer
Across 858 matched qualifying days, NAS100’s median daily percentage range was 1.79% versus 1.299% for SPX500—37.8% higher. NAS100 was wider on 95.7% of matched days, while their range-size correlation was 0.949.
Exact sources, gaps, and fingerprints
The Phase 3 analyzer read the same binary files served by FXAbsolute. It validated every timestamp and OHLC row, calculated each file’s SHA-256, and published both successful and excluded coverage counts before producing the findings.
Jan 4, 2021–Jul 31, 2026. Unmatched dates and under-covered periods were excluded; no values were filled.
Dukascopy index-CFD historical bid prices · bid prices
- UTC coverage bounds
- Jan 4, 2021–Aug 3, 2026
- Days with any candles
- 1,051 of 1,456 eligible days (72.2%)
- Qualified daily samples
- 1,044; 7 additional observed days failed the daily threshold
- Structural validation
- Header length matches · 0 malformed OHLC · 0 duplicates · 0 out-of-order · 0 off-minute
- Largest recorded gap
- 192.02 hours after Jan 10, 2021
- Repository provenance record
scripts/refetch_thin_assets.mjs· instrumentusatechidxusd- SHA-256
aa84e8d8687b2b6a670a1984ed57b8049f022dac688c5f3e89322deac94f0650
Dukascopy index-CFD historical bid prices · bid prices
- UTC coverage bounds
- Jan 4, 2021–Aug 3, 2026
- Days with any candles
- 1,072 of 1,456 eligible days (73.6%)
- Qualified daily samples
- 1,061; 11 additional observed days failed the daily threshold
- Structural validation
- Header length matches · 0 malformed OHLC · 0 duplicates · 0 out-of-order · 0 off-minute
- Largest recorded gap
- 192.02 hours after Mar 9, 2021
- Repository provenance record
scripts/refetch_thin_assets.mjs· instrumentusa500idxusd- SHA-256
ba02fab257d76a3427619fda214ba0238bb7a7da223baef0ccea627376f8bb87
Proof scope: the hashes identify the exact bytes measured, and the JSON exposes the displayed aggregates. This proves the reported calculations from these files. It does not prove complete calendar coverage, perfect upstream feeds, causal relationships, future regimes, or trading profitability.
Where the difference appeared
Every comparison uses percentage range as the headline measure and retains the native-unit median for chart scale. A closed or under-covered window is labeled unavailable rather than assigned a zero.
| UTC window | Matched blocks | NAS100 median | SPX500 median | A/B ratio | NAS100 higher | Range correlation |
|---|---|---|---|---|---|---|
| 00:00–03:59 UTCAsia open | 855 | 0.361%56.29 points · CI 0.344%–0.382% | 0.265%12.51 points · CI 0.251%–0.283% | 1.362× | 94.7% | 0.958 |
| 04:00–07:59 UTCAsia–London handoff | 855 | 0.403%62.98 points · CI 0.379%–0.417% | 0.286%13.99 points · CI 0.275%–0.306% | 1.409× | 93.5% | 0.943 |
| 08:00–11:59 UTCLondon morning | 859 | 0.492%77.25 points · CI 0.471%–0.518% | 0.366%17.55 points · CI 0.356%–0.389% | 1.344× | 92.1% | 0.948 |
| 12:00–15:59 UTCLondon–New York overlap | 855 | 1.18%185.58 points · CI 1.129%–1.236% | 0.807%37.69 points · CI 0.762%–0.835% | 1.461× | 96.3% | 0.929 |
| 16:00–19:59 UTCNew York afternoon | 829 | 0.936%147.8 points · CI 0.894%–0.977% | 0.72%33.89 points · CI 0.689%–0.755% | 1.3× | 95.2% | 0.976 |
| 20:00–23:59 UTCLate UTC | 0 | No qualifying paired blocks; no zero-volatility value was imputed. | ||||
NAS100’s larger normalized range persisted across open windows
The matched daily median ratio was 1.378×. NAS100’s median 95% interval was 1.699%–1.875%; SPX500’s was 1.238%–1.358%. NAS100 had the larger range on 95.7% of common days.
The 12:00–15:59 UTC block
The largest relative ratio occurred in the overlap block: 1.18% for NAS100 versus 0.807% for SPX500, a 1.461× ratio across 855 blocks.
Closed is not zero
Neither feed produced a qualifying paired 20:00–23:59 UTC block. The table reports it as unavailable. Assigning a zero would falsely mix market schedule with a measured low-volatility observation.
Non-contiguous index history
NAS100 had candles on 72.2% of eligible weekdays inside its bounds; SPX500 had 73.6%. The comparison uses only 858 matched qualified days. These are Dukascopy index-CFD bid feeds, not exchange prints or official cash-index bars.
Latest qualifying regime: high
On Jul 31, 2026, the trailing median of the latest 20 qualifying daily percentage ranges was 2.27%. For NAS100, low is at or below 1.301%, high is above 2.264%, and values between are classified normal.
These are within-market retrospective quartiles. A “high” regime for one market is not numerically equivalent to a “high” regime for another, and the label is not a forecast.
Latest qualifying regime: normal
On Jul 31, 2026, the trailing median of the latest 20 qualifying daily percentage ranges was 1.078%. For SPX500, low is at or below 0.931%, high is above 1.677%, and values between are classified normal.
These are within-market retrospective quartiles. A “high” regime for one market is not numerically equivalent to a “high” regime for another, and the label is not a forecast.
How Phase 3 was measured
(maximum high − minimum low) ÷ period open × 100. Native pips, points, or dollars remain published beside it.Reproduce the public report with npm run analyze:seo:phase3. Download the complete Phase 3 evidence JSON.
Limits before strategy testing
High–low range does not preserve the order of prices within a block, and range-size correlation is not return correlation. Wider movement can increase opportunity and risk simultaneously. These findings do not include entries, exits, spreads, slippage, financing, contract specifications, or a profitability model.
Replay the matched markets
Translate the distribution into a precise hypothesis with fixed windows, risk normalization, costs, and exit rules.
Questions this evidence can answer
Was NAS100 more volatile than SPX500?
Yes in this matched normalized sample: 1.79% versus 1.299%, a 37.8% ratio-of-medians difference.
Which session showed the largest NAS100–SPX500 difference?
12:00–15:59 UTC had the largest median ratio at 1.461×.
Why is 20:00–23:59 UTC unavailable?
Neither index-CFD file supplied at least 180 candles for a matched block in that fixed window. The study leaves it unavailable instead of imputing zero.
Does the 0.949 range correlation mean identical returns?
No. It compares the sizes of percentage ranges, not directional returns. It cannot establish a hedge ratio or synchronized direction.