UPDATE 1-Air France-KLM Oct traffic down 4.1 pct

* Capacity cuts outweigh falling traffic on most routes

* Unit revenues under pressure but decline is slower

* U.S. carriers show signs of slowing unit revenue declines

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PARIS, Nov 9 (Reuters) - Air France-KLM (AIRF.PA) passenger traffic fell 4.1 percent in October but the airline slashed the number of available seats by 5.6 percent, allowing it to fill its planes further and place a floor under average revenues.

The Franco-Dutch group said the passenger load factor, or proportion of seats sold, rose 1.3 percentage points to 82.5 percent in October, led by gains on its Americas network.

"Although unit revenues remained under pressure, they recorded a lesser decline," the airline said of the overall passenger trend in a statement on Monday.

Airlines report their traffic in a combination of passengers and the distance flown.