Format matters.
THE RULE
One row per record, one column per attribute, one value per cell.
WHAT THAT MEANS PRACTICALLY
Each transaction on its own row Each piece of information in its own column
WHAT BREAKS ANALYSIS
Several values in one cell Merged cells Blank rows separating sections Totals in the middle of data Headings repeated within the data Formatting used to convey meaning
THAT LAST ONE
A row coloured to mean something cannot be filtered or summed.
Add a column instead.
WHAT TO SEPARATE
Date and time from other text First and last names, if you will sort by either Quantity from unit
WHAT TO KEEP CONSISTENT
Date format Category names Spelling of anything you will group by
WHY CONSISTENCY MATTERS
Two spellings of the same category become two categories.
WHAT TO PUT ELSEWHERE
Totals, charts and notes.
Keep the data itself clean.
