Tutorial

Practical, copy-paste Excel formulas and QA steps to handle negative numbers and zeros when calculating percent change—avoid #DIV/0! and misleading results.

Prevent #DIV/0! in Excel with copy-paste formulas (IFERROR, IF, LET, LAMBDA). Keep percent metrics and charts accurate using NA(), 0, or placeholders.

Step-by-step guide to calculate percent change in Excel with copy-ready formulas, percentage formatting, absolute references, and error-handling tips.

Step-by-step Excel percent difference formula that handles negative and zero values—copy-paste formulas, zero-handling variants, and quick KPI examples.

Step-by-step guide to automate Excel division formulas and safely handle the Excel #DIV/0! error across ranges, Tables, LET/LAMBDA examples.

Practical best practices for IFERROR-style accuracy logs, append-only provenance, and privacy controls for spreadsheet AI agents—audit-ready guidance for SMBs.

Compare Excel Tables vs Named Ranges vs Power Query and learn which to use for scalability, refreshability, performance, and auditability — a practical SMB decision guide.

Practical rules for presenting CTR and CPA in dashboards — formatting, rounding, sample‑size flags, axis labels, and chart selection for marketing teams.

Step-by-step guide to perform element-wise array division in Excel 365 using =C5:C12/D5:D12. Fix #SPILL!, handle divide-by-zero, and aggregate results.

Prevent silent errors when using IFERROR—practical Excel & Google Sheets patterns (LET, helper columns, ERROR.TYPE), diagnostics and QA for SMB reporting.