Calculate percentage changes

On the sheet MonthlyKPIs I have last_month values in column B and this_month values in column C. Add a percentage change in column D calculated as (this_month - last_month) / last_month, formatted as a percentage with one decimal. Handle cases where last_month is zero by showing 'N/A'. Copy the formula down for 200 rows and label D1 'Pct change'.

Before I publish MonthlyKPIs to the leadership deck, make percentage changes easy to read and trustworthy. Move the percentage change into column D with one-decimal percentage formatting, show N/A where last_month is zero, color gains green and drops red, and add a top-line summary that shows the average percentage change and counts of N/A cells.

I calculated percentage change for MonthlyKPIs and many items show extreme values because last_month is zero. I worry leadership will misread these as explosive growth. I cannot change the underlying data. Should I show N/A, an explanatory footnote, or compute an alternative metric like absolute change? Which will be clearest for the CFO reviewing this afternoon, and how do I implement it now so the sheet is defensible?

Across reports, tiny bases and zeros create misleading percentage changes that cause back-and-forth with leadership. I want a policy to avoid this trap. Recommend a rule for when to show percentage change versus absolute change, a standard phrase to add in the sheet header explaining the rule, and a lightweight formula approach so analysts apply the rule consistently.