Snippet containing the relevant code for getting d3-tip to work in an Angular 2 app

bar-chart.component.ts

var d3 = require("d3");
var d3tip = require('d3-tip')(d3);
//---------------------------------
const tip = d3tip
  .attr('class', 'd3-tip')
  .offset([-10, 0])
  .html(function (d) {
    const date = new Date(d[0]);
    const year = date.getFullYear();
    const month = months[date.getMonth()];
    return d3.format("$,.1f")(d[1]) + "&nbsp;Billion<br>" + year + ' - ' + month + ""
  })