This is a Bullet Chart example that allows the user to update the chart automatically by updating the bulletdata2.json
file. This (online) example won't change, but if you download the file and read in conjunction with d3noob.org you will be able to impliment your own dynamic chart with it.
This is a follow on from the example that updated the charts with random data.
https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.17/d3.min.js