The Forecast Accuracy Ledger
Every month, when actual home prices publish, we grade the previous month's forecasts against them: ours, and Zillow's published forecast, metro by metro. Wins, losses, and the size of every miss go here. A forecaster who won't show you the scoreboard is asking for faith.
Monthly scoreboard
| Forecast month | Metros graded | Sialim median miss | Zillow median miss | Sialim wins | Zillow wins |
|---|---|---|---|---|---|
| June 2026 | 894 | 0.89% | 0.93% | 447 | 447 |
A "win" is the engine whose forecast landed closer to the realized value for that metro. Both engines are graded against identical realized values. Zillow forecast © Zillow, graded here for comparison.