Back to Notes
Craft
· November 2026
· 4 min read
Every number should be checkable
Why I attach a “way back” to every number I report — a note on trust in analytical work.
Written by Reyhaneh Ashrafi
linkedin.com/in/reyhaneh-ashrafi
The rule
In my bank project I computed more than fifty ratios, each with its own worksheet: input, source, formula, output. The rule was simple: every number must be checkable — someone other than me should be able to go from output to source and rebuild the same figure.
Why it matters
An uncheckable number is an opinion, not data. In analytical work, trust comes from repeatability, not confidence. When the way back is attached, the reader can disagree — and disagreement grounded in data is a gift, not a threat.
The rule works in life too: if I say “it is always so”, I must show where I saw it. Transparency of the path is candor — spreadsheet edition.
Key takeaways
- For every number: input, source, formula, output.
- Trust comes from repeatability.
- Data-grounded disagreement is a gift.