C9

C9 or C-9 may refer to:Hi-Point Models C9 and C9 Comp handguns.C9 machine gun, a Canadian variant of the FN Minimi.C9, an international standard paper size (40×57 mm), defined in  ISO 216.C9, the IATA code for Cirrus Airlines.C9, the designation of the FN Minimi machine gun used by the Canadian Forces and several other countries.The C-9A Nightingale/C-9B Skytrain II, a transport aircraft of the United States Air Force (Nightingale) or U.S. Naval Reserve and United States Marine Corps (Skytrain II). It's military version of McDonnell Douglas DC-9HMS C9, a C-class submarine of the Royal Navy.USS Montgomery (C-9), a protected cruiser of the United States Navy.C9 engine, by Caterpillar Inc.C9 is a global group of nine leading economists based in Zürich, Switzerland.C9, an extremely high "musical" note five octaves above Middle C. Only Georgia Brown (Brazilian singer) (not even Mariah Carey, Minnie Riperton or Adam Lopez) is reputed to sing this high.C9, a subsidiary of Champion sportswear company sold exclusively at Target stores.
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The modified S-I differences (ratios) are computed by subtracting C 7 from (additive models) or dividing C 7 into (multiplicative models) the C 1 series.
For more information, see X-11 Census Method II Seasonal Adjustment .