Unexpected automatic frequency detection with yearly data

[marcozanotti]

Hi @mdancho84 ,

I am encountering something unexpected in timetk::tk_get_frequency() when applied to yearly data.
For instance, you can check with the following code.

data <- tibble::tibble(
  "date" = seq.Date(as.Date("1960-01-01"), as.Date("2017-01-01"), by = "year"),
  "id" = "EU Population",
  "value" = tsibbledata::global_economy |> dplyr::filter(Country == "European Union") |> dplyr::pull(Population)
)
timetk::tk_get_frequency(data[["date"]])

timetk::tk_get_frequency() returns 5 in this example, while I would expect the frequency to be 1 for yearly data.

Thanks for your help.