Divergent stacked bars

by alcosbarco

HTML

<script src="https://cdn.amcharts.com/lib/4/core.js"></script>
<script src="https://cdn.amcharts.com/lib/4/charts.js"></script>
<script src="https://cdn.amcharts.com/lib/4/themes/animated.js"></script>
<div id="chartdiv"></div>

CSS

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}

#chartdiv {
  width: 100%;
  height: 500px;
}

JavaScript

/**
 * ---------------------------------------
 * This demo was created using amCharts 4.
 * 
 * For more information visit:
 * https://www.amcharts.com/
 * 
 * Documentation is available at:
 * https://www.amcharts.com/docs/v4/
 * ---------------------------------------
 */

// Themes begin
am4core.useTheme(am4themes_animated);
// Themes end

// Create chart instance
var chart = am4core.create("chartdiv", am4charts.XYChart);

// Title
var title = chart.titles.push(new am4core.Label());
title.text = "Research tools used by students";
title.fontSize = 25;
title.marginBottom = 15;

// Add data
chart.data = [{
  "category": "Search engines",
  "negative1": -0.1,
  "negative2": -0.9,
  "positive1": 5,
  "positive2": 94
}, {
  "category": "Online encyclopedias",
  "negative1": -2,
  "negative2": -4,
  "positive1": 19,
  "positive2": 75
}, {
  "category": "Peers",
  "negative1": -2,
  "negative2": -10,
  "positive1": 46,
  "positive2": 42
}, {
  "category": "Social media",
  "negative1": -2,
  "negative2": -13,
  "positive1": 33,
  "positive2": 52
}, {
  "category": "Study guides",
  "negative1": -6,
  "negative2": -19,
  "positive1": 34,
  "positive2": 41
}, {
  "category": "News websites",
  "negative1": -3,
  "negative2": -23,
  "positive1": 49,
  "positive2": 25
}, {
  "category": "Textbooks",
  "negative1": -5,
  "negative2": -28,
  "positive1": 49,
  "positive2": 18
}, {
  "category": "Librarian",
  "negative1": -14,
  "negative2": -34,
  "positive1": 37,
  "positive2": 16
}, {
  "category": "Printed books",
  "negative1": -9,
  "negative2": -41,
  "positive1": 38,
  "positive2": 12
}, {
  "category": "Databases",
  "negative1": -18,
  "negative2": -36,
  "positive1": 29,
  "positive2": 17
}, {
  "category": "Student search engines",
  "negative1": -17,
  "negative2": -39,
  "positive1": 34,
  "positive2": 10
}];


// Create axes
var categoryAxis = chart.yAxes.push(new am4charts.CategoryAxis());
categoryAxis.dataFields.category =...