# IOSX Tracking Error: Up vs Down Days

> Over the 90 days to Nov 4, 2026, IOSX missed two times AAPL's daily return by 15.2 basis points a day on average, on its closing price.

Data as of Nov 4, 2026. Rebuilt every trading night.

As of Nov 4, 2026 . Rebuilt every trading night.

## IOSX daily tracking

Over the 90 days to Nov 4, 2026, IOSX missed two times AAPL's daily return by 15.2 basis points a day on average, on its closing price.

| Window | Read on | Average daily miss, bp | Signed average, bp | Tracking error | Up days, bp | Down days, bp | Up less down, bp | Confidence |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 30 days to Nov 4, 2026: 18 of 22 days, from Oct 7, 2026 | NAV (stated) | 4.2 | −4.2 | 0.31% | −4.6 (10 days) | −3.6 (8 days) | −1.0 | Not enough days |
| 30 days to Nov 4, 2026, 22 daily returns | closing price | 10.3 | −4.5 | 2.37% | −9.2 (12 days) | +1.2 (10 days) | −10.4 | Not significant (t −1.6) |
| 90 days to Nov 4, 2026, 63 daily returns | closing price (stated) | 15.2 | −4.4 | 3.01% | −6.6 (33 days) | −2.0 (30 days) | −4.6 | Not significant (t −0.9) |

### IOSX's largest daily misses

The 5 days IOSX strayed furthest from its daily target in the 90 days to Nov 4, 2026, each on its NAV where ETFIQ holds it, else its closing price.

| # | Day | Read on | AAPL moved | Target | IOSX returned | Miss |
| --- | --- | --- | --- | --- | --- | --- |
| 1 | Aug 10, 2026 | closing price | −1.53% | −3.06% | −3.65% | −0.59 pts |
| 2 | Oct 2, 2026 | closing price | +1.02% | +2.04% | +1.66% | −0.38 pts |
| 3 | Aug 12, 2026 | closing price | −0.87% | −1.74% | −2.09% | −0.35 pts |
| 4 | Sep 1, 2026 | closing price | +2.61% | +5.23% | +4.91% | −0.31 pts |
| 5 | Aug 19, 2026 | closing price | +2.19% | +4.39% | +4.09% | −0.29 pts |

### Method

The daily miss is IOSX's return each day less two times AAPL's return that day. A basis point is a hundredth of a percentage point. Each window is read twice where ETFIQ holds both NAVs: on NAVs, and on closing prices. It is stated on the closing price because NAVs for 18 of the 63 sessions. IOSX ranks 87 of 494 2x leveraged ETFs on its 90-day average daily miss. Up days and down days split the miss by whether AAPL rose or fell; Significant means the gap is at least two standard errors from zero. The average miss carries its sign: a negative one is what the fund kept below its target each day, its fees and financing among it. 2 NAV days were held out, where the NAV and the closing price disagreed about the day: Oct 23, 2026, Oct 26, 2026. Not every fund here has traded for a year, and a number over eight months does not order against one over twelve. This page lists each fund with its window and dates instead of ranking them. It becomes a ranking on the night four of them share a full year. Every window ETFIQ can measure for IOSX is listed.

### Where to next

### Sources

Links are sources, not endorsements.

A ranking is not a recommendation or an opinion. ETFIQ is an independent publisher, not an adviser. Standards and sources

---

Source: ETFIQ, independent ETF data. Recomputed nightly from public filings and prices.
Cite: ETFIQ, IOSX daily tracking, listed by window, data as of Nov 4, 2026. https://etfiq.com/funds/iosx/tracking/
Licence: https://etfiq.com/license/ Data ETFIQ computes is free to use with attribution: ETFIQ (etfiq.com). Issuer data stays under its owner's terms.
HTML: https://etfiq.com/funds/iosx/tracking/