PARIGI, 13 novembre (Reuters) - French consumer prices were flat in October from September, giving a year-on-year inflation rate of 0.5 percent, EU-harmonised data released on Thursday by the INSEE national statistics office showed. KEY CPI DATA Index m/m (pct chg) y/y (pct chg) EU-harmonised (HICP) 115.58 0.0 0.5 National measure 127.84 0.0 0.5 National measure excl. tobacco 125.92 0.0 0.4 Core inflation 122.42 0.0 0.0 BACKGROUND French EU-harmonised inflation fell to a historical low of -0.8 percent in July 2009 and hit an all-time high of 4.0 percent in July 2008, according to INSEE's records going back to 1991. GRAPHIC link.reuters.com/wun37t FOR DETAILS FROM INSEE here. (Reporting by Paris newsroom)