Asia Pacific was hardest hit. Rents fell an average 16%, with huge dips in Singapore (45%), Hong Kong (35%) and Tokyo (21%). Still, these weren't the worst hit. Ho Chi Minh City saw rents fall 53%, due in large part to the addition of new space to the market.

In stark contrast, South America, the Middle East and Africa experienced the lowest rental rate decline; only 5%. Argentina was the only country in this region to see a double-digit decline.

For Central and Eastern Europe rental rates declined an average of 20%, while in North America rates fell by roughly 8%. The markets in India, likewise fell by 20%. The cities of Chennai and Mumbai both experienced a 30% decline in average rental rates.

As a result of the falling prices, Hong Kong dropped in rank from the most expensive city in the world to third place. Tokyo moved to first, followed by London's West End in second place.

Global rents are expected to reach the bottom of the barrel by the middle of 2010. Despite the disparaging figures, C&W executives in London believe companies will see better times in 2010 as the level of occupier confidence increases. Growth will slowly happen across the board but "The scale of the recovery is likely to vary not only from region to region but intra regionally too."

The report was compiled by David Hutchings, Elaine Rossall and Barrie David in C&W's London office.