Buick Grand National/GNX GNX
Showing appreciation momentum: +106% vs 12-mo avg, and sale prices -0.2%/mo.
What It's Actually Worth
Blended value of a standard 37 yr, 9k mi example, ~$128K now. The green line weighs confirmed auction sales most heavily (the amber dots — what cars actually hammered for), blends in fast-selling "just-missed" listings, and lightly smooths out month-to-month composition noise.
Did our model work? 65% direction calls right
Each faint amber line is a forecast we would have made at that point in the past (12-mo horizon), drawn against what actually happened (blue). Over 40 scored forecasts: 65% got the direction right, median value error ±44%.
Walk-forward: each ghost uses only data available at that date — no hindsight. Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.
Auction Scorecard gavel in range 9 in 10
We replayed 40 past auctions in this market — predicting each hammer price from market data before the sale (no hindsight). Typical miss: ±14%; the gavel landed inside our predicted range 9 in 10 of the time.
| Sold | Car | Our range | Hammer | |
|---|---|---|---|---|
| 2025-08-16 | 1987 · 28k mi | $75.6K–$246K | $157K | ✓ |
| 2025-08-07 | 1987 · 3k mi | $96.4K–$313K | $205K | ✓ |
| 2025-05-29 | 1987 · 55k mi | $62.8K–$204K | $140K | ✓ |
| 2025-05-12 | 1987 · 2k mi | $91.2K–$296K | $230K | ✓ |
| 2025-01-30 | 1987 · 82k mi | $54.1K–$176K | $102K | ✓ |
| 2024-10-23 | 1987 · 19k mi | $67.9K–$221K | $133K | ✓ |
| 2024-09-07 | 1987 · 13k mi | $74.7K–$243K | $130K | ✓ |
| 2024-07-27 | 1987 · 15k mi | $78.3K–$254K | $100K | ✓ |
Live now — calling it before the gavel
We're currently tracking 1 open auction in this market. Here's our predicted hammer range for each — check back after they close.
| Closes | Car | Source | Our predicted range |
|---|---|---|---|
| open | 1987 · 0k mi | classic | $79.7K–$369K ($171K) |
No-lookahead: predictions are made before each auction closes; the scorecard grades confirmed sold auctions only (no-sales excluded). A modeled estimate, not a guarantee. Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.
Where We Think It's Headed
Probability and range, not a single number. Wider = less certain (not bigger gains).
| Horizon | Direction | Probability | Confidence | Past accuracy |
|---|---|---|---|---|
| 6 mo | DOWN | 57% | Low | 63% |
| 12 mo | DOWN | 59% | Low | 65% |
| 24 mo | DOWN | 63% | Low | 86% |
Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.
Crystal Ball — What Leading Indicators Signal
Distinct from the trend forecast above: this blends all 8 leading indicators (each at its own lead time, de-duplicated so correlated ones don't double-count) into one signal. Leading indicators are collectively signaling higher over the next ~12 months (high conviction — 74% of weighted drivers agree), driven mainly by Initial Jobless Claims and Gold (futures), though Initial Jobless Claims points the other way.
Are the indicators agreeing?
Each bar is one driver's current push; longer = more weight. All one side = high conviction; split = low.
If You’d Bought in 2010
$100K invested 2010-01 → today (16.5 yrs), this car vs where else you could've put the money. Rebased to 100 at the start; the dashed line is inflation (break-even).
What This Market Follows
Specialty-car prices don't move in a vacuum. These economic indicators have historically led this market — tap one to see it shifted forward by its lead time, overlaid on the value line.
Trade-Weighted Dollar Index leads by about 6 months (moves against this market, correlation 0.85). Shown shifted forward 6 months so its turns line up with the market's.
Why We Think This
Current Inventory Snapshot
Recent Signals & Alerts
- vin returned higher VIN relisted +$179,840 vs prior
- vin returned higher VIN relisted +$179,840 vs prior
- vin returned higher VIN relisted +$179,840 vs prior
- vin returned higher VIN relisted +$179,840 vs prior
- vin returned higher VIN relisted +$179,840 vs prior
- inventory spike Inventory spiked (robust z=3.4)
Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.