Sebastien
4,057 recorded births · active 1971–2025
Compare Sebastien →Living-age distribution
The median living Sebastien is 18. If you meet a Sebastien, there's about a 70% chance they're between 8 and 29 years old.
Popularity arc
Peak Sebastien: 2007. Down 41% from peak.
Projected: the dashed 10-year forecast (Holt damped-trend exponential smoothing, fit to recent years), with a shaded 95% interval.
Gender balance
Sebastien is almost always given to male babies — 100% male.
Rarity
Sebastien ranks #4,848 out of 105,966 names ever recorded by the SSA.
Geographic fingerprint
Sebastiens are 1.1x more common in the West than the national average.
Predictive modeling
Three statistical models, all fit to Sebastien's own SSA history plus the historical behavior of every other name in the dataset.
Peak popularity prediction
Sebastien's modeled peak was #2,319 in 2001 — its trend isn't projected to beat that.
Projects the trend forward, then converts share into rank using this year's popularity distribution.
This forecasts Sebastien's share of births by fitting a damped-trend model to its last 54 years of data and projecting 10 years forward with a widening uncertainty band. Each projected share is then translated into a rank by comparing it against 2025's actual name-popularity distribution — so the model implicitly assumes the overall shape of that distribution doesn't shift much over the forecast window. Its trend is projected to stay below its historic best over the next 10 years, so the model treats 2001 as its peak. Milestone probabilities come from how much of each year's uncertainty band clears that milestone's rank, combined across years as if they were independent — which slightly overstates the odds for names sitting right at a threshold, since a good year is usually followed by another good year rather than an independent coin flip.Name life-cycle stage
A rule-based classifier over recent growth, momentum, and peak proximity.
Sebastien's popularity has been easing lower recently, though not sharply enough to call it a steep decline.
Popularity survival model
Once a name reaches a rank tier, how long does it typically stay there before falling out?
Built from a Kaplan-Meier survival curve: every historical run any name has ever had above this tier, with runs still ongoing today counted as still in progress rather than as an exit.Sebastien isn't currently in the Top 100 tier. Estimated chance of entering it in the forecast window: 0%.
If Sebastien enters Top 100, chance it's still there after:
Names that do enter Top 100 have historically stayed a median of ~19 years. Based on 668 historical Top 100 runs across every name in the dataset.