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Basic Information

• Mastgroups File
• Mastdata File
• Locating the Correct Data File
• Locating Corresponding Columns Associating with Selected Item_Id
• Data Type Applied

• Mastgroups File Format
• Mastdata File Format
• Unit_Reference File Format
• Source File Format
• Footnote Reference File Format
• Flag_Reference File Format

Open Excel file Mastgroups. It will have two columns KeyAbr and Descript. In column KeyAbr, the user will find a standard three character abbreviation or acronymn for its official title as listed under Descript. Try to become familiar with the three character abbreviation or acronymn being used.

Example:
If a user is interested in the descript of Agriculture - NAICS then they should write down or become familiar with the abbreviation or acronymn of AGN. This will come into play when the user next opens the Mastdata file.

Next, open file Mastdata. This Excel file has two columns with column names of Item_id and Item_description (row 1).

Column Item_id provides a name of an Excel column, for example, AFN110197D. The AFN of AFN110197D indicates this is AFN type data. The 110 of AFN110197D indicates the group-series number of AFN data. The 197 of AFN110197D indicates this is data of the year 1997, and D stands for data. Likewise, 202 of AFN110202D indicates this is data of the year 2002.

The user should examine the titles in column Item_description and locate the description they are looking for. Once a user locates an Item_description they are looking for, make note of the Item_id corresponding to that Item_description. That Item_id is column name the user will be looking for in one of the actual Excel data files.

Example:
If a user is interested in file AGE110197D, they examine Excel files AGE01.xls, AGE02.xls, or AGE03.xls, or they may use zip file AGE.zip. The columns of files AGE01.xls, AGE02.xls, and AGE03.xls are listed in alphabetical order. For example, for AGE series, the columns would range from AGE010180D to AGE430202D in AGE01, AGE430203D to AGE830205D in AGE02, and AGE830206D to AGE900206D in AGE03. Therefore, column AGE110197D would be located in the AGE010180D to AGE430202D range, which can be found in files AGE01.xls orAGE.zip.

Note that sum topics only have one related file, and some may have 2,3,4 or more files related to the key topic. The example above in reference to AGE has three files AGE01, AGE02, or AGE03.

Every data file, e.g. AGE01, AGE02, or AGE03, has its first two columns as Areaname and STCOU. STCOU stands for the State-County code of a specific region (county, state, federal). Each Item_id, e.g., AFN110197D has four columns (flag, data values, footkey1, footkey2). The name ending with F is the flag column of the selected Item_id, for example, AFN110197F. The name ending with D is the datavalue column of the selected Item_id, i.e., AFN110197D. The name ending with N1 is the Footnote1 column of the selected Item_id, i.e., AFN110197N1. The name ending with N2 is the Footnote2 column of the selected Item_id, i.e., AFN110197N2.

Example:
Each table selected (Item_id) has four corresponding columns of data: flag, datavalue, footkey1, footkey2 e.g. AFN110197F, AFN110197D, AFN110197N1, and AFN110197N2.

Moreover, the flag column of a selected Item_id is integer data and the datavalue column of a selected Item_id is double (numeric) data. The Footkey1 and Footkey2 columns of a selected Item_id are text data. The STCOU column is text data, and the Areaname column is text data.

Source: U.S. Census Bureau