* Nine-month net profit down to 8.5 million euros
* Windfall tax, recession hit profit
* Sales down 21.8 percent to 1.3 billion euros
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ATHENS, Nov 29 (Reuters) - Ellaktor, Greece's largest construction group, reported an 88 percent fall in nine-month net profit, hurt by a windfall tax and lower revenues from concessions due to recession at home.
Net profit came in at 8.5 million euros ($11.2 million), compared with a forecast for 13.9 million in a Reuters poll.
The contractor receives tolls from the operation of the Athens ring road Attiki Odos and Rio-Antirio, a bridge connecting western Greece to the Peloponnese peninsula, which account for about two thirds of operating profit.
Turnover fell 21.8 percent to 1.3 billion euros on reduced construction backlog, as Greece has not tendered any major projects in the past year, while revenue fron concessions fell 10.6 percent as austerity measures hit household budgets.
Ellaktor has a 2.6 billion euro backlog of projects and is also active in waste management, wind energy and real estate.
The stock trades at 12 times its estimated 2009 earnings, compared with a multiple of 12.5 for French company Vinci and 18.7 for German group Hochtief, data from Reuters I/B/E/S showed. (Reporting by Angeliki Koutantou; Editing by Dan Lalor) ($1 = 0.7606 euro)