To forecast industry growth, you can set up several growth models and examine the results under different assumptions. Growth models allow you to develop an idea of when the growth inflexion will appear and what will drive it to appear.
You need to gather data on key indicators to chart the growth. These indicators will most likely be industry sales, industry segment sales and demographic data.
You can develop forecasts for a new industry by referring similar industries. For example, if you want to forecast growth of digital audio tape technology, you may start your projection from the market of CD or cassette-tape technology.