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What I learned about clean data
Most dashboard problems are data problems. Three habits that save me hours every week.
Every dashboard I've built taught me the same lesson: the chart is the easy part.
1. Fix it at the source
If a date is typed three different ways, don't patch it in the report. Fix the input sheet, or add a data-validation rule so it can't happen again.
2. Keep one ID per thing
Reusing an asset ID after disposal looks harmless until two years of history merge into one row.
3. Write down what "done" means
Before cleaning, list the checks the data must pass: no blanks in key columns, no duplicate IDs, dates in one format. Then you know when to stop.