Options Skew Analytics

GRMN options analytics

GRMN · Stock

Data as of 22 September 2026 (end of day)

No metrics could be computed for this session

Its next earnings report is 2026-10-28, before the open.

Current readings

30-day ATM implied volatilityⓘ
—
25-delta risk reversalⓘ
—
25-delta butterflyⓘ
—
Term structure slopeⓘ
—

Where 30-day implied volatility sits

Against 25 prior sessions (one-year window)

Not enough history in this window to place the current reading.

IV percentile, 1 year
—
IV rank, 1 year
—
IV percentile, 2 years
—
IV rank, 2 years
—

Rank is the position between the lowest and highest readings in the window, so a single past extreme pins everything after it near one end. Percentile is the share of sessions below the current reading and is unaffected by how far that extreme reached. Both are withheld when the window holds fewer than 180 sessions.

Session detail

Underlying close
$284.67
30-day implied forward
—
60-day ATM IV
—
90-day ATM IV
33.60%
180-day ATM IV
—
Expirations used
3
Total open interest
5,126
Put / call open interest
0.22

The forward is derived from put-call parity on the strikes nearest the money, not taken from the underlying close. It is what every moneyness and delta on this page is measured against.

30-day at-the-money implied volatility

Last 225 sessions

20%30%40%50%60%70%2024-10-16 — 30-day ATM IV 31%2024-10-17 — 30-day ATM IV 31%2024-10-18 — 30-day ATM IV 31%2024-10-21 — 30-day ATM IV 31%2024-10-22 — 30-day ATM IV 32%2024-10-23 — 30-day ATM IV 32%2024-10-24 — 30-day ATM IV 32%2024-10-25 — 30-day ATM IV 32%2024-10-28 — 30-day ATM IV 32%2024-10-29 — 30-day ATM IV 39%2025-01-22 — 30-day ATM IV 38%2025-01-23 — 30-day ATM IV 39%2025-01-24 — 30-day ATM IV 40%2025-01-29 — 30-day ATM IV 40%2025-02-03 — 30-day ATM IV 43%2025-02-05 — 30-day ATM IV 43%2025-02-07 — 30-day ATM IV 43%2025-02-11 — 30-day ATM IV 45%2025-02-12 — 30-day ATM IV 47%2025-02-18 — 30-day ATM IV 46%2025-04-08 — 30-day ATM IV 60%2025-04-23 — 30-day ATM IV 45%2025-04-24 — 30-day ATM IV 43%2025-04-29 — 30-day ATM IV 49%2025-04-30 — 30-day ATM IV 33%16 Oct24 Oct24 Jan12 Feb30 Apr
Show the underlying numbers (most recent 120)
Session30-day ATM IV25-delta RRTerm slopeClose
2026-09-22———$284.67
2026-09-21———$280.31
2026-09-18———$274.06
2026-09-17———$275.35
2026-09-16———$276.93
2026-09-15———$278.97
2026-09-14———$280.38
2026-09-11———$282.67
2026-09-10———$272.20
2026-09-09———$272.18
2026-09-08———$275.68
2026-09-04———$277.03
2026-09-03———$277.18
2026-09-02———$276.04
2026-09-01———$275.17
2026-08-31———$284.11
2026-08-28———$285.19
2026-08-27———$289.87
2026-08-26———$289.02
2026-08-25———$288.45
2026-08-24———$291.25
2025-06-30———$208.72
2025-06-27———$208.36
2025-06-26———$205.15
2025-06-25———$203.54
2025-06-24———$205.08
2025-06-23———$201.74
2025-06-20———$200.01
2025-06-18———$198.30
2025-06-17———$197.78
2025-06-16———$203.92
2025-06-13———$201.32
2025-06-12———$208.39
2025-06-11———$209.13
2025-06-10———$210.12
2025-06-09———$208.29
2025-06-06———$207.45
2025-06-05———$205.48
2025-06-04———$204.95
2025-06-03———$204.50
2025-06-02———$202.95
2025-05-30———$202.97
2025-05-29———$202.84
2025-05-28———$201.93
2025-05-27———$205.51
2025-05-23———$200.59
2025-05-22———$201.58
2025-05-21———$200.74
2025-05-20———$203.76
2025-05-19———$204.90
2025-05-16———$205.28
2025-05-15———$201.92
2025-05-14———$200.58
2025-05-13———$200.44
2025-05-12———$197.98
2025-05-09———$191.43
2025-05-08———$190.41
2025-05-07———$188.26
2025-05-06———$187.14
2025-05-05———$190.15
2025-05-02———$191.78
2025-05-01———$186.78
2025-04-3032.80%+3.790.957$186.87
2025-04-2948.89%+9.470.787$204.10
2025-04-28———$200.63
2025-04-25———$198.96
2025-04-2442.81%+7.880.841$199.11
2025-04-2345.27%+5.870.812$193.83
2025-04-22———$191.41
2025-04-21———$186.83
2025-04-17———$190.61
2025-04-16———$188.96
2025-04-15———$192.31
2025-04-14———$192.10
2025-04-11———$189.78
2025-04-10———$186.83
2025-04-09———$192.71
2025-04-0859.72%+22.150.753$173.63
2025-04-07———$180.86
2025-04-04———$178.46
2025-04-03———$185.34
2025-04-02———$218.07
2025-04-01———$217.57
2025-03-31———$217.13
2025-03-28———$213.66
2025-03-27———$216.96
2025-03-26———$216.83
2025-03-25———$218.57
2025-03-24———$214.47
2025-03-21———$210.19
2025-03-20———$208.71
2025-03-19———$208.77
2025-03-18———$206.63
2025-03-17———$212.44
2025-03-14———$213.90
2025-03-13———$209.37
2025-03-12———$215.61
2025-03-11———$213.21
2025-03-10———$215.32
2025-03-07———$219.34
2025-03-06———$221.91
2025-03-05———$224.81
2025-03-04———$220.12
2025-03-03———$226.22
2025-02-28———$228.93
2025-02-27———$224.06
2025-02-26———$226.92
2025-02-25———$226.04
2025-02-24———$222.81
2025-02-21———$224.71
2025-02-20———$229.01
2025-02-19———$241.93
2025-02-1845.75%+3.710.789$214.78
2025-02-14———$212.62
2025-02-13———$210.23
2025-02-1246.57%+4.38—$209.63
2025-02-1144.78%+4.880.716$211.57
2025-02-10———$215.73
2025-02-0742.86%+3.980.770$217.67
2025-02-06———$219.78

The chart covers every session in the archive, 225 in total. The table lists the most recent 120.

25-delta risk reversal

Last 225 sessions

-10.00.010.020.030.02024-10-16 — 25-delta RR (volatility points) 2.42024-10-17 — 25-delta RR (volatility points) 3.52024-10-18 — 25-delta RR (volatility points) 2.62024-10-21 — 25-delta RR (volatility points) 2.72024-10-22 — 25-delta RR (volatility points) 2.72024-10-23 — 25-delta RR (volatility points) 2.82024-10-24 — 25-delta RR (volatility points) 3.32024-10-25 — 25-delta RR (volatility points) 2.72024-10-28 — 25-delta RR (volatility points) 2.52024-10-29 — 25-delta RR (volatility points) 4.52025-01-22 — 25-delta RR (volatility points) 3.32025-01-23 — 25-delta RR (volatility points) 3.32025-01-24 — 25-delta RR (volatility points) 2.52025-01-29 — 25-delta RR (volatility points) 3.52025-02-03 — 25-delta RR (volatility points) 2.52025-02-05 — 25-delta RR (volatility points) 0.72025-02-07 — 25-delta RR (volatility points) 4.02025-02-11 — 25-delta RR (volatility points) 4.92025-02-12 — 25-delta RR (volatility points) 4.42025-02-18 — 25-delta RR (volatility points) 3.72025-04-08 — 25-delta RR (volatility points) 22.22025-04-23 — 25-delta RR (volatility points) 5.92025-04-24 — 25-delta RR (volatility points) 7.92025-04-29 — 25-delta RR (volatility points) 9.52025-04-30 — 25-delta RR (volatility points) 3.816 Oct24 Oct24 Jan12 Feb30 Apr

The dashed line marks zero, where the 25-delta put and call carry the same implied volatility.

Skew curve

Implied volatility by delta, front expirations

Implied volatility by delta

87d (2026-12-18) · 115d (2027-01-15) · 150d (2027-02-19)

30%32%34%36%38%2026-12-18 (87d) — 20Δ C — IV 31.71%2026-12-18 (87d) — 25Δ C — IV 31.38%2026-12-18 (87d) — 30Δ C — IV 31.65%2026-12-18 (87d) — 35Δ C — IV 32.20%2026-12-18 (87d) — 40Δ C — IV 33.01%2026-12-18 (87d) — 45Δ C — IV 33.49%2026-12-18 (87d) — ATM — IV 33.87%2026-12-18 (87d) — 45Δ P — IV 34.43%2026-12-18 (87d) — 40Δ P — IV 34.99%2026-12-18 (87d) — 35Δ P — IV 35.51%2026-12-18 (87d) — 30Δ P — IV 35.61%2026-12-18 (87d) — 25Δ P — IV 35.72%2026-12-18 (87d) — 20Δ P — IV 36.22%87d2027-01-15 (115d) — 20Δ C — IV 32.01%2027-01-15 (115d) — 25Δ C — IV 31.91%2027-01-15 (115d) — 30Δ C — IV 32.09%2027-01-15 (115d) — 35Δ C — IV 30.97%2027-01-15 (115d) — 40Δ C — IV 31.09%2027-01-15 (115d) — 45Δ C — IV 31.38%2027-01-15 (115d) — ATM — IV 31.88%2027-01-15 (115d) — 45Δ P — IV 32.42%2027-01-15 (115d) — 40Δ P — IV 32.89%2027-01-15 (115d) — 35Δ P — IV 33.24%2027-01-15 (115d) — 30Δ P — IV 33.70%2027-01-15 (115d) — 25Δ P — IV 34.38%115d2027-02-19 (150d) — 25Δ C — IV 31.26%2027-02-19 (150d) — 30Δ C — IV 31.55%2027-02-19 (150d) — 35Δ C — IV 31.80%2027-02-19 (150d) — 40Δ C — IV 32.35%2027-02-19 (150d) — 45Δ C — IV 32.89%2027-02-19 (150d) — ATM — IV 33.69%2027-02-19 (150d) — 45Δ P — IV 34.30%2027-02-19 (150d) — 40Δ P — IV 34.65%2027-02-19 (150d) — 35Δ P — IV 35.03%2027-02-19 (150d) — 30Δ P — IV 35.62%2027-02-19 (150d) — 25Δ P — IV 36.50%150d10Δ C25Δ CATM25Δ P10Δ Pout-of-the-money calls ← delta → out-of-the-money puts

The axis is call delta. Readings to the right of the dashed centre line are taken from the out-of-the-money put at that strike, which is the contract whose quote the volatility was solved from. Points are only plotted where surviving quotes bracket the delta on both sides; nothing is extrapolated past the last traded strike.

Show the underlying numbers
Delta87d115d150d
20Δ call31.71%32.01%—
25Δ call31.38%31.91%31.26%
30Δ call31.65%32.09%31.55%
35Δ call32.20%30.97%31.80%
40Δ call33.01%31.09%32.35%
45Δ call33.49%31.38%32.89%
ATM33.87%31.88%33.69%
45Δ put34.43%32.42%34.30%
40Δ put34.99%32.89%34.65%
35Δ put35.51%33.24%35.03%
30Δ put35.61%33.70%35.62%
25Δ put35.72%34.38%36.50%
20Δ put36.22%——

Wing readings by expiration

ExpirationDaysForwardATM IV25Δ put25Δ callRRButterflyQuotes
2026-12-1887$285.8633.87%35.72%31.38%+4.34-0.329
2027-01-15115$285.9531.88%34.38%31.91%+2.46+1.2610
2027-02-19150$287.5133.69%36.50%31.26%+5.24+0.199

Each curve above is one expiration. The vertical position is implied volatility; the horizontal position is the delta of the contract it was read from. For US equities the curve normally slopes upward to the right, meaning out-of-the-money puts carry higher implied volatility than equidistant calls.

The 25-delta risk reversal summarises that slope as a single number: the 25-delta put volatility minus the 25-delta call volatility. The butterfly summarises the curvature: the average of the two wings minus the at-the-money reading.

Term structure

At-the-money implied volatility by expiration

At-the-money implied volatility by expiration

3 listed expirations produced a usable reading

31%32%33%34%35%2026-12-18 — 87 days — at-the-money IV 33.87%2027-01-15 — 115 days — at-the-money IV 31.88%2027-02-19 — 150 days — at-the-money IV 33.69%90days to expiration

The horizontal axis is the square root of days to expiration, which is the scale volatility lives on. A curve that is flat in variance terms plots as a straight line here rather than bending sharply through the front week.

Show the underlying numbers
ExpirationDaysForwardATM IVATM strikeQuotes used
2026-12-1887 days$285.8633.87%$289.799
2027-01-15115 days$285.9531.88%$290.5610
2027-02-19150 days$287.5133.69%$294.299

Constant maturities

Interpolated between the bracketing listed expirations, in total variance

30 days
—
60 days
—
90 days
33.60%
180 days
—

Interpolation is linear in total variance, not in volatility. Interpolating volatility directly implies a forward variance that can be negative between two expirations. A tenor beyond the longest listed expiration is reported as unavailable rather than extrapolated.

Term structure slope

Last 225 sessions

0.600.700.800.901.001.102024-10-16 — 90-day over 30-day 0.792024-10-17 — 90-day over 30-day 0.812024-10-18 — 90-day over 30-day 0.792024-10-21 — 90-day over 30-day 0.802024-10-22 — 90-day over 30-day 0.812024-10-23 — 90-day over 30-day 0.822024-10-24 — 90-day over 30-day 0.822024-10-25 — 90-day over 30-day 0.812024-10-28 — 90-day over 30-day 0.802025-01-22 — 90-day over 30-day 0.742025-01-23 — 90-day over 30-day 0.782025-01-29 — 90-day over 30-day 0.742025-02-05 — 90-day over 30-day 0.752025-02-07 — 90-day over 30-day 0.772025-02-11 — 90-day over 30-day 0.722025-02-18 — 90-day over 30-day 0.792025-04-08 — 90-day over 30-day 0.752025-04-23 — 90-day over 30-day 0.812025-04-24 — 90-day over 30-day 0.842025-04-29 — 90-day over 30-day 0.792025-04-30 — 90-day over 30-day 0.9616 Oct23 Oct23 Jan18 Feb30 Apr

The dashed line marks 1.00, where the 90-day and 30-day at-the-money volatilities are equal. Above it the longer tenor carries the higher volatility.

The term structure is the at-the-money implied volatility of each listed expiration, plotted against how far away that expiration is. Its usual shape for a calm underlying slopes gently upward, because a longer horizon admits more uncertainty.

It inverts when the market prices a dated event: an expiration that captures a scheduled announcement carries the variance of that event on top of ordinary trading, so a shorter contract can print a higher volatility than a longer one.

Earnings

What the options priced in before each report, and what happened

Next report

2026-10-28Before the openAnnounced

How the pricing has held up

Over the last 2 reports

Landed inside the implied band
0 of 2
0% — about 68% is what an exactly-priced event gives
Mean implied move
11.1%
Mean move that happened
17.9%
absolute

Reports

Newest first. The implied move is one standard deviation, priced from the session before the release.

ReportSessionImplied ±RealisedRealised / implied
2026-07-29Before the open———
2026-04-29Before the open———
2026-02-18Before the open———
2025-10-29Before the open———
2025-07-30Before the open———
2025-02-19Before the open11.9%+12.6%1.07×
2024-10-30Before the open10.3%+23.2%2.27×
2024-07-31Before the open———
2024-05-01Before the open———
2024-02-21Before the open———
2023-11-01Before the open———

The implied move is read from the at-the-money straddle on the first expiration strictly after the report date, converted to a one-standard-deviation move and divided by the forward. Realised moves are the close-to-close return across the event, measured from the session before the release to the session after it.

Report dates that have already happened come from the company’s own 8-K filing and are exact. A date still in the future is either one the company has announced, or an estimate from its reporting cadence.