{
  "id": 18880611,
  "title": "How does FORECAST.ETS predict the December sales peak?",
  "url": "https://urgent.news/2026/11/08/comment-forecast-ets-prevoit-il-le-pic-de-ventes-de-decembre",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-11-08T06:32:31.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/bestaitools-fr/comment-forecastets-prevoit-il-le-pic-de-ventes-de-decembre--18mn"
  },
  "original_language": "fr",
  "account": "A Python script has been created to replicate the functionality of the Forecast Sheet in a spreadsheet application, specifically the `FORECAST.ETS` function. The script uses the Holt-Winters method with additive seasonality to forecast sales data for a small shop over 36 months. The results show that the script's forecast matches the spreadsheet's forecast to within 2% over 12 months, with some differences in the confidence intervals. The script also demonstrates the importance of including seasonality in the forecast, as a linear model without seasonality produces significantly different results.",
  "summary": "FORECAST.ETS(...) looks like magic: give it three years of monthly sales and it sends back a December higher than all the other months, a January that drops and a confidence interval around both. Underneath, there is an exponential smoothing with a trend and a repeating season, a method from the late 1950s that fits in about forty lines. The Forecast…",
  "key_points": [
    "FORECAST.ETS predicts December sales peak",
    "36-month monthly sales table input",
    "Predicted value for December 2026 is 20.654"
  ],
  "editors_take": "Utiliser la fonction FORECAST.ETS permet de transformer des données historiques de ventes en projections chiffrées et en intervalles de confiance pour anticiper les tendances saisonnières futures.",
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}