Edit in JSFiddle

var stxx = new CIQ.ChartEngine({
  container: $$$(".chartContainer")
});

function showEvents() {
  var markerTypes = ["dividend", "news", "earnings"],
    newNode;
  for (var i = 0; i < stxx.masterData.length - 10; i += 5) {
    var r = Math.floor(Math.random() * (markerTypes.length));
    if (r == markerTypes.length) continue; // randomize
    newNode = $$$("#stxEventPrototype").cloneNode(true);
    newNode.id = null;
    newNode.innerHTML = markerTypes[r].capitalize().charAt(0);
    CIQ.appendClassName(newNode, markerTypes[r]);

    new CIQ.Marker({
      stx: stxx,
      xPositioner: "date",
      x: stxx.masterData[i].DT,
      label: "events",
      node: newNode,
      panelName: "\u200cvolume\u200c"
    });
  }
  stxx.draw();
}

stxx.loadChart("SPY", sampleData);
CIQ.Studies.addStudy(stxx, "volume");
showEvents();
<div class="chartContainer" style="width:100%;height:400px;position:relative;"></div>

<!--[if IE 8]><script>alert("This template is not compatible with IE8");</script><![endif]-->

<script src="https://jsfiddle.chartiq.com/chart/js/chartiq.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<script src="https://jsfiddle.chartiq.com/chart/js/componentUI.js"></script>
<script src="https://jsfiddle.chartiq.com/chart/examples/data/STX_SAMPLE_DAILY.js"></script>

<div id="stxEventPrototype" class="myEvents">
</div>
.myEvents {
  position: absolute;
  text-align: center;
  width: 20px;
  height: 20px;
  line-height: 20px;
  color: white;
}

/*style dividents to be a blue circle*/

.myEvents.dividend {
  background-color: blue;
  -webkit-border-radius: 50%;
  -moz-border-radius: 50%;
  -ms-border-radius: 50%;
  border-radius: 50%;
}

/*style news to be a small red square*/

.myEvents.news {
  background-color: red;
  width: 15px;
  height: 15px;
  line-height: 15px;
}

.myEvents.earnings {
  background-color: purple;
  border: 5px solid yellow;
}

/*style to be a brown Rhombus*/

.myEvents.rhombus .shape {
  position: absolute;
  width: 20px;
  height: 20px;
  left: 0px;
  background-color: yellow;
  border: 2px solid black;
  color: black;
  -webkit-transform: rotate(45deg);
  /* Saf3.1+, Chrome */
  -moz-transform: rotate(45deg);
  /* FF3.5+ */
  -ms-transform: rotate(45deg);
  /* IE9 */
  -o-transform: rotate(45deg);
  /* Opera 10.5 */
  transform: rotate(45deg);
}

.myEvents.rhombus .label {
  position: absolute;
  width: 20px;
  height: 20px;
  left: 2px;
  /* offset to center the label */
}

.myEvents.hoverMarker {
  background-color: pink;
  border: 2px solid black;
}

/*  create some rudimentary styling for our tooltip class */

.tooltip {
  display: inline;
  position: relative;
}

.hoverMarker:hover .tooltip:after {
  background: #333;
  background: rgba(0, 0, 0, .8);
  border-radius: 5px;
  bottom: 26px;
  color: #fff;
  content: attr(title);
  left: 20%;
  padding: 5px 15px;
  position: absolute;
  z-index: 98;
  width: 30px;
  content: attr(title);
}

.hoverMarker:hover .tooltip:before {
  border: solid;
  border-color: #333 transparent;
  border-width: 11px 6px 0 6px;
  bottom: 20px;
  content: "";
  left: 50%;
  position: absolute;
  z-index: 99;
}