C 19

C19 or C-19 may be:C-19 Alpha, three aircraft purchased by the US Army Air Corps in 1931Boeing C-19, military designation for Boeing 747-100 seriesA type of Electric power connector
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The values in C 18 are used to adjust the original (adjusted) series (in A 3 or B 1 ). Specifically, the values in C 18 are subtracted from (additive model) or divided into (multiplicative model) the original series.
For more information, see X-11 Census Method II Seasonal Adjustment .