That’s the trade-weighted RMB index. And it’s key to FX markets in 2016 and beyond (read up).
That decline is absolutely critical to the post Shanghai Accord stability.
A Fed hike will turn it on its head (why do you think – besides oil prices – the Fed didn’t hike in March?) – and that’s already starting to happen. Incidentally, it’s also the biggest story of the day.
See here for the full scoop.