Level 8 · From numbers to a takeaway

What, how much, so what

A takeaway that a manager can act on has three parts:

Part	Answers	Example
What	What is the main result?	Business accounts bring a large share of revenue
How much	Which number backs it?	26% of orders, 52% of revenue
So what	What does it mean for a decision?	Losing one hurts as much as losing several consumers

Without “how much” it’s a description of a chart. Without “so what” it’s a fact nobody can use. Compare “The chart shows revenue by segment. Business is high.” with “Business accounts placed 26% of 2025’s completed orders but brought 52% of revenue.” The second one can be acted on.

Compute the numbers, never copy them

Every number in a takeaway should come from code that runs right before it, formatted by an f-string. Then a re-run with new data updates the sentence too, and nobody has to retype 52% from a chart.

order_share = is_b.mean()                               # 0.2638 → "26%"
f"{order_share:.0%}"                                    # '26%'
f"{706.9:,.0f}"                                         # '707'
f"{1200321.6:,.0f}"                                     # '1,200,322'

:.0% multiplies by 100, rounds to whole percents and adds the sign. :,.0f adds thousands separators. Printing the sentence (print(result)) shows it exactly as the reader will see it.

Writing it in a notebook

In a notebook, the takeaway goes in a Markdown cell under the chart, not in a code comment. Markdown is plain text with light markup: # for a title, ## for a section, **bold** for the key numbers, - for a bullet list, and a table with a |---|---| line under its header. Give every question its own heading, then code, chart and takeaway in that order. Put all imports in the first cell and check the notebook with Restart & Run All: if it fails from top to bottom, it isn’t done.

Other kinds of takeaways

• A decision about the data: what you decided, why, and its impact. “We kept the 370 outlier orders: they’re real business purchases, and dropping them would remove a large share of revenue.”
• A correlation: strength, direction, the word “associated”, and what’s not related.
• A recommendation: an action verb, a concrete place, the number behind it. “Give business accounts a named contact: they bring 52% of revenue from 26% of orders.”

Common mistakes

• Describing the chart (“the chart shows…”) instead of stating the finding.
• Rounding by hand or pasting numbers from a chart.
• Leaving out the denominator: “52% of revenue” of what, in which year?
• Writing “causes” for a correlation, or giving a recommendation without the number behind it.