# ISUL Tracking Error: Up vs Down Days

> Over the 90 days to Nov 4, 2026, ISUL missed two times ISRG's daily return by 13.1 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.

## ISUL daily tracking

Over the 90 days to Nov 4, 2026, ISUL missed two times ISRG's daily return by 13.1 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: 11 of 22 days, from Oct 16, 2026 | NAV | 2.6 | −2.6 | 0.37% | −1.4 (6 days) | −4.0 (5 days) | +2.7 | Not enough days |
| 30 days to Nov 4, 2026, 22 daily returns | closing price (stated) | 18.1 | −1.6 | 3.92% | +1.5 (13 days) | −5.9 (9 days) | +7.4 | Not enough days |
| 90 days to Nov 4, 2026: 12 of 63 days, from Sep 11, 2026 | NAV | 3.1 | −3.1 | 0.45% | −2.4 (7 days) | −4.0 (5 days) | +1.7 | Not enough days |
| 90 days to Nov 4, 2026, 63 daily returns | closing price (stated) | 13.1 | −2.7 | 2.78% | −1.3 (36 days) | −4.6 (26 days) | +3.4 | Not significant (t 0.8) |
| 180 days to Nov 4, 2026, 124 daily returns | closing price (stated) | 16.6 | −3.1 | 3.89% | −4.0 (67 days) | −2.0 (56 days) | −2.0 | Not significant (t −0.5) |
| 1 year to Nov 4, 2026, 251 daily returns | closing price (stated) | 16.1 | −3.3 | 3.50% | −3.3 (124 days) | −3.3 (126 days) | 0.0 | Not significant (t −0.0) |

### ISUL's largest daily misses

The 5 days ISUL strayed furthest from its daily target in the 1 year to Nov 4, 2026, each on its NAV where ETFIQ holds it, else its closing price.

| # | Day | Read on | ISRG moved | Target | ISUL returned | Miss |
| --- | --- | --- | --- | --- | --- | --- |
| 1 | Jul 24, 2026 | closing price | +1.65% | +3.30% | +1.92% | −1.38 pts |
| 2 | Jul 23, 2026 | closing price | −2.54% | −5.09% | −4.25% | +0.84 pts |
| 3 | Mar 2, 2026 | closing price | −1.44% | −2.88% | −2.21% | +0.67 pts |
| 4 | May 18, 2026 | closing price | +4.46% | +8.93% | +8.35% | −0.58 pts |
| 5 | Jun 2, 2026 | closing price | −2.42% | −4.83% | −5.35% | −0.52 pts |

### Method

The daily miss is ISUL's return each day less two times ISRG'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 12 of the 63 sessions. ISUL ranks 54 of 494 2x leveraged ETFs on its 90-day average daily miss. Up days and down days split the miss by whether ISRG 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. 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 ISUL 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

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Source: ETFIQ, independent ETF data. Recomputed nightly from public filings and prices.
Cite: ETFIQ, ISUL daily tracking, listed by window, data as of Nov 4, 2026. https://etfiq.com/funds/isul/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/isul/tracking/