The turmoil of the past year has taken the final toll on several once-mighty real estate investment trusts, which have lost close to 90% of their market value and are no longer eligible to hold a position in any key sharemarket index.

It is a major blow for any stock to be dropped from an index as its precludes them from being bought by any index-based investor.

Generally, a fall out of the index leads to even more selling as managers adjust their index portfolios accordingly.

The latest round of removals by ratings agency Standard & Poor's has taken Valad and Macquarie CountryWide from the S&P/ASX 100. Both stocks have been hard hit this year as they battle falling asset values and, in the case of Macquarie CountryWide, tenants in its US shopping malls going into Chapter 11 bankruptcy.

The agency has also removed troubled Centro from the major S&P/ASX All Australian 200 index. Also out of that index is APN European Retail Property Trust, which has been under pressure due to its exposure to the European market.

The Age