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  * __
  * [ pandas.DatetimeIndex ](pandas.DatetimeIndex.html)
  * pandas.Datet... 

#  pandas.DatetimeIndex.is_year_start  #

_ property  _ DatetimeIndex.  is_year_start  [ [source]
](https://github.com/pandas-
dev/pandas/blob/v2.2.2/pandas/core/indexes/extension.py#L67-L75) #

    

Indicate whether the date is the first day of a year.

Returns  :

    

Series or DatetimeIndex

    

The same type as the original data with boolean values. Series will have the
same name and index. DatetimeIndex will have the same name.

See also

[ ` is_year_end  `
](pandas.DatetimeIndex.is_year_end.html#pandas.DatetimeIndex.is_year_end
"pandas.DatetimeIndex.is_year_end")

    

Similar property indicating the last day of the year.

Examples

This method is available on Series with datetime values under the ` .dt  `
accessor, and directly on DatetimeIndex.

    
    
    >>> dates = pd.Series(pd.date_range("2017-12-30", periods=3))
    >>> dates
    0   2017-12-30
    1   2017-12-31
    2   2018-01-01
    dtype: datetime64[ns]
    
    
    
    >>> dates.dt.is_year_start
    0    False
    1    False
    2    True
    dtype: bool
    
    
    
    >>> idx = pd.date_range("2017-12-30", periods=3)
    >>>