At the other end of the spectrum is London's West End, where the market commands $156.89 per sf, and Tokyo's Inner and Outer Central Districts, the No. 2 most expensive market, where class A space goes for $147.05 per sf and $127.54 per sf, respectively.

The study, which covered the last quarter of 2000, ranked 154 markets. Other markets in the top 10 include London, Hong Kong, Paris and Bombay, India.

The US markets that made the top 20 most expensive markets included Silicon Valley, sixth; San Francisco, ninth; Midtown Manhattan, 10th; and Boston, 15th. Rates climbed to $87.48 per sf in Silicon Valley, $73.75 per sf in San Francisco, $64.63 per sf in Midtown Manhattan, and $55.36 per sf in Boston.