Keep one record per row
Use a consistent structure: one row per transaction or observation, and one column per attribute. Avoid mixing summary totals with the underlying records.
Give every column a clear heading
Use short, descriptive names and keep the headers in a single row. Avoid merged cells in the source data you intend to filter or analyse.
Be consistent with data types
A date should be a date, and a numeric amount should be a number. Check for text values masquerading as numbers before building formulas or summaries.
Turn the range into a table
Excel tables give your dataset a useful structure and make filtering easier. In desktop Excel for Windows, select your range and press Ctrl+T, then confirm the header setting.
Keep an untouched source
Preserve the original export before making changes. Work in a separate sheet or file so you can compare your results and investigate unexpected differences.
A practical guide from the MSExpert learning library. Application features and shortcuts may vary by version and platform.