A^Analytical data
AI^Analytical data; from the literature or  government;  incomplete documentation
AR^Analytical data; derived by linear regression
AS^Analytical data; derived by summation of components with source code 1 or 7
BD^Based on same food; Drained solids from solids and liquids or vice versa (canned fruits and vegetables)
BFAN^Based on another form of the food or similar food; Concentration adjustment; Ash; Retention factors not used
BFCN^Based on another form of the food or similar food; Concentration adjustment; Carbohydrate; Retention factors not used
BFFN^Based on another form of the food or similar food; Concentration adjustment; Fat; Retention factors not used
BFFY^Based on another form of the food or similar food; Concentration adjustment; Fat; Retention factors used
BFNN^Based on another form of the food or similar food; Concentration adjustment; Non-fat solids; Retention factors not used
BFNY^Based on another form of the food or similar food; Concentration adjustment; Non-fat solids; Retentions factors used
BFPN^Based on another form of the food or similar food; Concentration adjustment; Protein; Retention factors not used
BFPY^Based on another form of the food or similar food; Concentration adjustment; Protein; Retention factors used
BFSN^Based on another form of the food or similar food; Concentration adjustment; Solids; Retention factors not used
BFSY^Based on another form of the food or similar food; Concentration adjustment; Solids; Retention factors used
BFYN^Based on another form of the food or similar food; Concentration adjustment; Yield; Retention factors not used
BFZN^Based on another form of the food or similar food; Concentration adjustment; No adjustment; Retention factors not used
BFZY^Based on another form of the food or similar food; Concentration adjustment; No adjustment; Retention factors used
BNA^Based on another form of the same food or similar food: constituents normalized to total; vitamin A
CAAN^Calculated from different food; From average values for food category; Ash; Retention factors not used
CAFN^Calculated from different food; From average values for food category; Fat; Retention factors not used
CASN^Calculated from different food; From average values for food category; Solids; Retention factors not used
CAZN^Calculated from different food; From average values for food category; No adjustment; Retention factors not used
DA^Concentration adjustment using factor; derived from analytical data
DI^Concentration adjustment using factor; derived from imputed data
FLA^Estimated formulation based on ingredient list; Linear program used to estimate ingredients; Analytical data
FLC^Estimated formulation based on ingredient list; Linear program used to estimate ingredients; Claim on label/serving
FLM^Estimated formulation based on ingredient list; Linear program used to estimate ingredients; Manuf. Calc. data/100
JA^Aggregated data involving combinations of data with only source codes 1 and 12 and/or 13
JO^Aggregated data involving combinations of data with different source codes when at least one code is not 1, 12, or 6.
LC^Label claim (back calculated from label by NDL staff; Calculated from label claim/serving (g or %RDI)
MA^Manufacturer supplied(industry or trade association); Analytical data, incomplete documentation
MC^Manufacturer supplied; Calculated by manufacturer or unknown if analytical or calculated
ML^Manufacturer supplied; Value upon which manufacturer based label claim for fortified/enriched nutrient
NC^Nutrient that is based on other nutrient/s; calculated rather than analyzed
NP^Nutrient that is based on other nutrient/s; calculated by difference or summed (with or without activity factors)
Ex. Proximate component other than CHO by difference.
Vitamin A calculated from components when one of the component values is not source code 1 or 7
NR^Nutrient that is based on other nutrient/s; value used directly, ex. Nut.#204 from Nut.#298
O^Other procedure used from imputing
PAE^Based on physical composition; Derived from analytical data; Estimated physical composition
PAK^Based on physical composition; Derived from analytical data; Known physical composition
PIE^Based on physical composition; Derived from imputed data; Estimated physical composition
PIK^Based on physical composition; Derived from imputed data; Known physical composition
RA^Recipe; Approximate ingredient proportions (ex. combination of several recipes)
RC^Recipe; Cookbook
RF^Recipe; Formulary of standard products (formulary or standards of identity)
RK^Recipe; Known formulation (dissection data or proprietary formulation)
RKA^Recipe; Known formulation; No adjustments applied, combination of source codes 1, 12, and/or 6.
RKI^Recipe;Known formulation;No adjustments applied, combination of source codes which includes codes other than 1,12,or 6
RP^Recipe; Per package directions (ex. refrigerated dough, toast, cake mix)
RPA^Recipe; Per package directions; No adjustments applied, combination of source codes 1, 12, and/or 6.
RPI^Recipe;Per package directions;No adjustments applied, combination of source codes which incl codes other than 1,12,or 6
S^Product standard, such as enrichment level specified in CFR or AMS commodity standard
T^Taken from another source--other tables of food composition
Z^Assumed zero (Insignificant amount or not naturally occurring in a food, such as fiber in meat)
