Linear Scale with Decimals

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
    svg { width: 100%; height: 100%; }
    .container {
      height: 300px;
      width: 70%;
      margin: auto;
      display: flex;
      justify-content: space-around;
      align-items: center;
    }
    .code-container {
      width: 100%;
      text-align: center;
    }
    .code-container > code {
      font-size: 18px;
    }
    .plus, .minus {
      cursor: pointer;
      font-weight: bold;
      display:inline-block;
      width: 50px;
      height: 50px;
      border-radius: 50%;
    }
    .plus {
      background-color: springgreen;
    }
    .minus {
			background-color: crimson;
    }
    .plus > p, .minus > p {
      padding-left: 10px;
      margin-top: -7px;
      font-weight: bold;
      color: white;
      font-size: 50px;
      width: 80px;
    }
    .minus > p {
      padding-left: 16px;
    }
    .value, .domain, .range {
      display: inline;
      font-size: 18px;
    }
    .domain, .range {
      max-width: 50px;
    }
    .domain {
      margin-right: 60px;
    }
  </style>
</head>

<body>
  <div class="container">
    <div class="minus"><p>-</p></div>
    Domain:
    <div class="domain"></div>
    Range:
    <div class="range"></div>
    <div class="plus"><p>+</p></div>
  </div>
  
  <div class="code-container">
    <code class="scale">
      d3.scale.linear().domain([6, 16]).range([0.9, 0.005]);
    </code>
  </div>
  
  <script>
    var margin = {top: 20, right: 10, bottom: 20, left: 10};
    var width = 960 - margin.left - margin.right;
    var height = 500 - margin.top - margin.bottom;
    
    var scale = d3.scale.linear().domain([6, 16]).range([0.9, 0.005]);
		var currentValue = 6;
    
    var format = d3.format('.5g');
    
    var domain = d3.select('.domain').text(currentValue);
    var range = d3.select('.range').text(scale(currentValue));
    
    d3.select('.minus').on('click', function() {
      currentValue -= 1;
      domain.text(currentValue);
      range.text(scale(currentValue));
    })
    
    d3.select('.plus').on('click', function() {
      currentValue += 1;
      domain.text(currentValue);
   		range.text(format(scale(currentValue)));
    })
    
    
  </script>
</body>

https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js