Erro ao fazer resultado.plot()

Não estou conseguindo entender o motivo do erro no seguinte codigo:

resultado = seasonal_decompose([chocolura['vendas']], freq=1)
ax = resultado.plot()

Estou tendo como saída o erro:

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-519-0fe700893215> in <module>
----> 1 resultado = seasonal_decompose([chocolura['vendas']], freq=1)
      2 ax = resultado.plot()

~\anaconda3\lib\site-packages\pandas\util\_decorators.py in wrapper(*args, **kwargs)
    212                 else:
    213                     kwargs[new_arg_name] = new_arg_value
--> 214             return func(*args, **kwargs)
    215 
    216         return cast(F, wrapper)

~\anaconda3\lib\site-packages\statsmodels\tsa\seasonal.py in seasonal_decompose(x, model, filt, period, two_sided, extrapolate_trend)
    146         raise ValueError('x must have 2 complete cycles requires {0} '
    147                          'observations. x only has {1} '
--> 148                          'observation(s)'.format(2 * pfreq, x.shape[0]))
    149 
    150     if filt is None:

ValueError: x must have 2 complete cycles requires 2 observations. x only has 1 observation(s)