The Turkish lira hit a record low against its US counterpart last week. The fall was driven by concern generally over China's prospects but also by local, political uncertainty. There's pressure on the central bank to raise interest rates but there's no sign of such a move just yet.

The Polish zloty, on the other hand, has appeared remarkably resilient in recent days. Ken says economic fundamentals in the country are looking good and that's been reflected in the currency's performance.