LONDON (Reuters) - Commercial property values dropped by a further 4.6 percent in October, extending the market's price correction to 27.4 percent from its summer 2007 peak, data from property consultant CB Richard Ellis showed.

The CB Richard Ellis Monthly Index for October showed average commercial property prices have sunk 17.6 percent in the year to date, as valuers adjust prices in line with Britain's depressing economic outlook.

CB Richard Ellis said the average all property one-month total return -- rental income and capital growth combined -- fell to minus 4.1 percent in October.

All property rents declined 0.5 percent over the month, with further contractions in financial and business services activity pushing Central London office rents down by 2.5 percent.

Reflecting last month's sharp downturn in consumer spending, retail property was the worst-performing property segment in October, generating a minus 4.5 percent one-month total return compared with minus 4 percent for offices and minus 3.1 percent for industrial real estate.

CB Richard Ellis is one of the biggest contributors to benchmark valuation data from Investment Property Databank IPD.L, which is used as the basis for property derivatives trading. IPD is due to report its latest monthly data on Friday.

(Reporting by Sinead Cruise)

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