Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

How do freight derivatives like Forward Freight Agreements (FFAs) work?
To answer this part of the question: "How can you build an index based on shipping routes - what is the significance of that? Indexes are traditionally built based on companies: e.g. S&P Index is a basket of companies whose price varies. But here you need a basket of FFA contracts from different oil firms (Shell, BP), 5 year Shell FFA's, 10 year shell FFA's. Where do routes enter the picture? Let the tanker any route he feels like." No, you don't get a basket of FFA contracts from given companies (such as Shell and BP). What you get are rates assessed by a panel of brokers for the main tanker routes (especially in the tanker market, there are comparatively few standard routes, because the major oil loading areas are also comparatively few). The panel will assess the spot and future markets on a daily basis, and issue the rates accordingly.