.. This document is auto-generated by the altair-gallery extension. Do not modify directly.

.. _gallery_histogram_with_a_global_mean_overlay:


Histogram with a Global Mean Overlay
------------------------------------
This example shows a histogram with a global mean overlay.


.. altair-plot::
    :code-below:

    
    import altair as alt
    from vega_datasets import data

    source = data.movies.url

    bar = alt.Chart(source).mark_bar().encode(
        alt.X('IMDB_Rating:Q', bin=True, axis=None),
        alt.Y('count()')
    )

    rule = alt.Chart(source).mark_rule(color='red').encode(
        x='mean(IMDB_Rating):Q',
        size=alt.value(5)
    )

    bar + rule


.. toctree::
   :hidden: