Diverging Stacked Bar Chart

This example shows a diverging stacked bar chart for sentiments towards a set of eight questions, displayed as percentages with neutral responses straddling the 0% mark.

import altair as alt

source = alt.pd.DataFrame([
      {
        "question": "Question 1",
        "type": "Strongly disagree",
        "value": 24,
        "percentage": 0.7,
        "percentage_start": -19.1,
        "percentage_end": -18.4
      },
      {
        "question": "Question 1",
        "type": "Disagree",
        "value": 294,
        "percentage": 9.1,
        "percentage_start": -18.4,
        "percentage_end": -9.2
      },
      {
        "question": "Question 1",
        "type": "Neither agree nor disagree",
        "value": 594,
        "percentage": 18.5,
        "percentage_start": -9.2,
        "percentage_end": 9.2
      },
      {
        "question": "Question 1",
        "type": "Agree",
        "value": 1927,
        "percentage": 59.9,
        "percentage_start": 9.2,
        "percentage_end": 69.2
      },
      {
        "question": "Question 1",
        "type": "Strongly agree",
        "value": 376,
        "percentage": 11.7,
        "percentage_start": 69.2,
        "percentage_end": 80.9
      },

      {
        "question": "Question 2",
        "type": "Strongly disagree",
        "value": 2,
        "percentage": 18.2,
        "percentage_start": -36.4,
        "percentage_end": -18.2
      },
      {
        "question": "Question 2",
        "type": "Disagree",
        "value": 2,
        "percentage": 18.2,
        "percentage_start": -18.2,
        "percentage_end": 0
      },
      {
        "question": "Question 2",
        "type": "Neither agree nor disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": 0,
        "percentage_end": 0
      },
      {
        "question": "Question 2",
        "type": "Agree",
        "value": 7,
        "percentage": 63.6,
        "percentage_start": 0,
        "percentage_end": 63.6
      },
      {
        "question": "Question 2",
        "type": "Strongly agree",
        "value": 11,
        "percentage": 0,
        "percentage_start": 63.6,
        "percentage_end": 63.6
      },

      {
        "question": "Question 3",
        "type": "Strongly disagree",
        "value": 2,
        "percentage": 20,
        "percentage_start": -30,
        "percentage_end": -10
      },
      {
        "question": "Question 3",
        "type": "Disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": -10,
        "percentage_end": -10
      },
      {
        "question": "Question 3",
        "type": "Neither agree nor disagree",
        "value": 2,
        "percentage": 20,
        "percentage_start": -10,
        "percentage_end": 10
      },
      {
        "question": "Question 3",
        "type": "Agree",
        "value": 4,
        "percentage": 40,
        "percentage_start": 10,
        "percentage_end": 50
      },
      {
        "question": "Question 3",
        "type": "Strongly agree",
        "value": 2,
        "percentage": 20,
        "percentage_start": 50,
        "percentage_end": 70
      },

      {
        "question": "Question 4",
        "type": "Strongly disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": -15.6,
        "percentage_end": -15.6
      },
      {
        "question": "Question 4",
        "type": "Disagree",
        "value": 2,
        "percentage": 12.5,
        "percentage_start": -15.6,
        "percentage_end": -3.1
      },
      {
        "question": "Question 4",
        "type": "Neither agree nor disagree",
        "value": 1,
        "percentage": 6.3,
        "percentage_start": -3.1,
        "percentage_end": 3.1
      },
      {
        "question": "Question 4",
        "type": "Agree",
        "value": 7,
        "percentage": 43.8,
        "percentage_start": 3.1,
        "percentage_end": 46.9
      },
      {
        "question": "Question 4",
        "type": "Strongly agree",
        "value": 6,
        "percentage": 37.5,
        "percentage_start": 46.9,
        "percentage_end": 84.4
      },

      {
        "question": "Question 5",
        "type": "Strongly disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": -10.4,
        "percentage_end": -10.4
      },
      {
        "question": "Question 5",
        "type": "Disagree",
        "value": 1,
        "percentage": 4.2,
        "percentage_start": -10.4,
        "percentage_end": -6.3
      },
      {
        "question": "Question 5",
        "type": "Neither agree nor disagree",
        "value": 3,
        "percentage": 12.5,
        "percentage_start": -6.3,
        "percentage_end": 6.3
      },
      {
        "question": "Question 5",
        "type": "Agree",
        "value": 16,
        "percentage": 66.7,
        "percentage_start": 6.3,
        "percentage_end": 72.9
      },
      {
        "question": "Question 5",
        "type": "Strongly agree",
        "value": 4,
        "percentage": 16.7,
        "percentage_start": 72.9,
        "percentage_end": 89.6
      },

      {
        "question": "Question 6",
        "type": "Strongly disagree",
        "value": 1,
        "percentage": 6.3,
        "percentage_start": -18.8,
        "percentage_end": -12.5
      },
      {
        "question": "Question 6",
        "type": "Disagree",
        "value": 1,
        "percentage": 6.3,
        "percentage_start": -12.5,
        "percentage_end": -6.3
      },
      {
        "question": "Question 6",
        "type": "Neither agree nor disagree",
        "value": 2,
        "percentage": 12.5,
        "percentage_start": -6.3,
        "percentage_end": 6.3
      },
      {
        "question": "Question 6",
        "type": "Agree",
        "value": 9,
        "percentage": 56.3,
        "percentage_start": 6.3,
        "percentage_end": 62.5
      },
      {
        "question": "Question 6",
        "type": "Strongly agree",
        "value": 3,
        "percentage": 18.8,
        "percentage_start": 62.5,
        "percentage_end": 81.3
      },

      {
        "question": "Question 7",
        "type": "Strongly disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": -10,
        "percentage_end": -10
      },
      {
        "question": "Question 7",
        "type": "Disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": -10,
        "percentage_end": -10
      },
      {
        "question": "Question 7",
        "type": "Neither agree nor disagree",
        "value": 1,
        "percentage": 20,
        "percentage_start": -10,
        "percentage_end": 10
      },
      {
        "question": "Question 7",
        "type": "Agree",
        "value": 4,
        "percentage": 80,
        "percentage_start": 10,
        "percentage_end": 90
      },
      {
        "question": "Question 7",
        "type": "Strongly agree",
        "value": 0,
        "percentage": 0,
        "percentage_start": 90,
        "percentage_end": 90
      },

      {
        "question": "Question 8",
        "type": "Strongly disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": 0,
        "percentage_end": 0
      },
      {
        "question": "Question 8",
        "type": "Disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": 0,
        "percentage_end": 0
      },
      {
        "question": "Question 8",
        "type": "Neither agree nor disagree",
        "value": 0,
        "percentage": 0,
        "percentage_start": 0,
        "percentage_end": 0
      },
      {
        "question": "Question 8",
        "type": "Agree",
        "value": 0,
        "percentage": 0,
        "percentage_start": 0,
        "percentage_end": 0
      },
      {
        "question": "Question 8",
        "type": "Strongly agree",
        "value": 2,
        "percentage": 100,
        "percentage_start": 0,
        "percentage_end": 100
      }
])

color_scale = alt.Scale(
    domain=[
        "Strongly disagree",
        "Disagree",
        "Neither agree nor disagree",
        "Agree",
        "Strongly agree"
    ],
    range=["#c30d24", "#f3a583", "#cccccc", "#94c6da", "#1770ab"]
)

y_axis = alt.Axis(
    title='Question',
    offset=5,
    ticks=False,
    minExtent=60,
    domain=False
)

alt.Chart(source).mark_bar().encode(
    x='percentage_start:Q',
    x2='percentage_end:Q',
    y=alt.Y('question:N', axis=y_axis),
    color=alt.Color(
        'type:N',
        legend=alt.Legend( title='Response'),
        scale=color_scale,
    )
)