C4

C4 or C-4 may refer to:C-4 (explosive), a type of plastic explosiveIn biology:C4 carbon fixation, a pathway for carbon fixation in photosynthesisFourth cervical vertebra or C4 spinal nerve, in human anatomyComplement component 4In vehicles:USS C-4 (SS-15), a United States C class submarine of the United States NavyHMS C4, a British C class submarine of the Royal NavyUSS Philadelphia (C-4), a protected cruiser of the United States NavyC-4 Academe, the military version of Gulfstream I twin turboprop business aircraftAEG C.IV, a German World War I reconnaissance aircraftCitroën C4, a car made by CitroënChevrolet Corvette C4, the fourth production design of the Chevrolet CorvetteFord C4 transmission, an automatic transmissionC-4, the US Army designation of the Ford Trimotor.Canadair North Star C-4 aircraft derived from the Douglas DC-4
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To obtain the refined S-I differences (ratios), the values in C 2 are subtracted from (additive model) or divided into (multiplicative model) the modified series in C 1 .
For more information, see X-11 Census Method II Seasonal Adjustment .