multiline chart

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body {padding: 100px; margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
    svg {
      border: 1px solid #ddd;
    }
  </style>
</head>

<body>
  <script>
    var margin = { top: 10, right: 10, bottom: 10, left: 10 };
    var outerWidth = 350;
    var outerHeight = 200;
    var width = outerWidth - margin.left - margin.right;
    var height = outerHeight - margin.bottom - margin.top;
    
    var svg = d3.select("body").append("svg")
      .attr("width", outerWidth)
      .attr("height", outerHeight)
    .append('g')
    	.attr('transform', `translate(${margin.left}, ${margin.top})`);
    
    var parseDate = d3.timeParse('%d-%b-%y');
    
    var x = d3.scaleTime()
    	.range([0, width]);
    
    var y = d3.scaleLinear()
    	.range([height, 0]);
    
    var line = d3.line()
    	.curve(d3.curveCatmullRom)
    	.x(d => x(d.date))
    	.y(d => y(d.value));
    
    var targetLine = d3.line()
    	.curve(d3.curveCatmullRom)
    	.x(d => x(d.date))
    	.y(d => y(d.target));
    
    function draw(error, data) {
      if (error) return;
      
      data.forEach(d => {
        d.value = +d.value;
        d.target = +d.target;
        d.date = parseDate(d.date);
      });

x.domain(d3.extent(data, d => d.date));
      y.domain([0, d3.max(data, d => d.value)]);
      
     	svg.append('g')
        .append('path')
      	.datum(data)
      	.attr('stroke', 'skyblue')
      	.attr('opacity', '0.6')
      	.attr('stroke-width', '1.5')
      	.attr('stroke-dasharray', '5')
      	.attr('fill', 'none')
      	.attr('d', line);
      
      var g = svg.append('g');
      
        g.append('path')
      	.datum(data)
      	.attr('stroke', 'skyblue')
        .attr('stroke-width', '1.5')
      	.attr('fill', 'none')
      	.attr('d', targetLine);
      
      var last = data.filter(d => d.target).slice(-1).pop();
      console.log(last);
      g.append('circle')
      	.attr('stroke', 'skyblue')
      	.attr('stroke-width', '1.5')
      	.attr('fill', 'none')
      	.attr('cx', x(last.date) + 5 )
      	.attr('cy', y(last.target))
      	.attr('r', 4);
    }
    
    d3.csv('data.csv', draw);
  </script>
</body>

https://d3js.org/d3.v4.min.js