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Statistical function

FORECAST.ETS.SEASONALITY

Returns the length of the repeating pattern Excel detects in a time series.

Rarely usedDifficulty 1500 · AdvancedUsage rank #396 of 520
Practice · 2 questions →

When to use it

The length of the repeating pattern Excel detects in a time series, in periods. 0 means no seasonality found.

The shape of it

Syntax
=FORECAST.ETS.SEASONALITY(values, timeline, [data_completion], [aggregation])

Worked examples

  • Monthly data

    =FORECAST.ETS.SEASONALITY(B2:B37,A2:A37) → 12

    Monthly data with a yearly cycle.

  • Daily data

    =FORECAST.ETS.SEASONALITY(B2:B105,A2:A105) → 7

    Daily data with a weekly cycle.

  • No pattern

    =FORECAST.ETS.SEASONALITY(B2:B37,A2:A37,1) → 0

    Data with no pattern; here with missing points filled by zeros rather than interpolated.

Worth knowing

  • Run it first to see what FORECAST.ETS will assume.
  • Needs at least two full cycles of data.
  • Pass the result into FORECAST.ETS explicitly if you want it fixed.

Where it goes wrong

  • Returns 0 when the series is too short or noisy to detect a cycle.
  • #VALUE! for an irregular timeline.

Related

AVERAGECOUNTCOUNTACOUNTIFCOUNTIFSMAX

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