Excel files are notorious for being able to store many kinds of data, charts, formulas, and other content in any style and layout a user chooses. While it is difficult to to document all types of Excel files, DDI is well suited to document well formatted Excel files containing tabular data.
There are two types of data that a well formatted Excel file may contain.
- Measurement data
- Aggregate data
DDI describes both measurements data (microdata) and aggregate data. Measurement data is arranged in defined columns, with an optional first row containing the column headers or names. Each row of measurement data contains a set of measures or values. Aggregate data is normally arranged in a cube or pivot table, with a set of dimensions and aggregate measurements.
An Excel file can contain multiple sheets. A well formatted Excel file will have one dataset per sheet. This allows describing each sheet as a tabular or aggregate dataset, and to document relationships between them.
Tools
An Excel file may be easily documented using the free Colectica for Excel addin. This tool integrates into Excel to allow documenting Excel workbooks and sheets using the DDI standard. It provides an extra panel to record more detailed descriptions of the columns and variables of a dataset, and stores the additional information directly within the Excel file. The tool will also create pdf data dictionaries from documented Excel files. The Professional version of Colectica for Excel can also import and document datasets saved in proprietary statistical package formats, such as SPSS and Stata.
Colectica for Excel
http://docs.colectica.com/excel/
http://www.colectica.com/software/colecticaforexcel