[tim]

the vacancy rate is very high for frankfurt - in fact it's probably the highest ever, but in comparison to other cities abroad (new york, london, shanghai, etc..) it's still not that bad. germany had always very low vacancy rates - when london had 10% or new york 15%, cities like frankfurt or munich only had 5% or even as low as 1%...
in germany the real estate industry speaks about a crisis when they mention a 10-15% vacancy rate - in other cities it's the usual vacancy rate.
still, despite the relatively high vacancy rate, the frankfurt real estate market is still the healthiest in germany. frankfurt has always been an exception to the rule - not only in the world of the real estate...