Period comparisonAgainst whatLive

A change is only a change
against the right stretch.

A period is a pair of dates, everything on the screen is fetched for it, and the comparison is the equally long stretch immediately before. A week against the month before it is not a change — it is two different questions.

Measured, not estimated EU-hosted Read-only by default

This month€2,521net
The month before€2,460equal length
Change+€61decomposed
Every cardsame datesno exceptions

01 / The case for it

A change against the wrong window is not a change.

Without it

Compare seven days to the calendar month before them and the week will always look small. Compare a part-month to a full one and it always looks like a decline. The comparison decides the conclusion, and most tools never say what theirs is.

What Profflow does

The equal stretch immediately before, and the whole screen moves.

A period is a pair of dates. Everything is fetched for exactly those dates — the KPIs, the waterfall, the margin, the chart — and the comparison is the same number of days ending the day before yours starts.

02 / What it looks like

Against the equal stretch before

On the screenJuly against June, on the same figures
FigureChangeThis period · the one before
Net profit€61€2,521 · €2,460
Revenue€30€7,940 · €7,910
Advertising−€45€1,180 · €1,135
Margin€231.8% · 31.1% — points, not per cent

Every card on the screen is fetched for the same pair of dates, and the comparison is the equally long stretch immediately before it. No card is comparing against something else.

Equal length, immediately before, on every figure on the page. A headline reporting a month beside a chart reporting a week is a page that cannot be quoted, and that is what this used to be before the period drove the whole screen.

03 / Worth understanding

What “up 12%” has to mean

A comparison is only as honest as its baseline

Against last month, against the same month last year, against the previous 30 days — these give three different answers, and a dashboard that does not say which it used has not made a comparison.

Every figure moves together

Change the dates and the whole screen refetches: profit, products, channels, VAT, the lot. Cards that update independently eventually show two periods at once and nobody notices.

Points are not per cent

A margin that goes from 31.1% to 31.8% has moved 0.7 points, not 2.3 per cent. Both sentences are arithmetically defensible and only one of them is what anybody means, so the product writes points.

04 / What it is built from

Period comparison is assembled
from accounts you already run.

01Order dates02Refund dates03Fee posting dates04Ad spend by day05Fixed costs, spread06The comparable stretch before
Period comparison
One period, one screenA like-for-like comparisonCustom rangesDates from local parts

05 / How it is worked out

From the account
to the figure on the screen.

  1. 01PicksA pair of dates — today, seven days, a month, a quarter or your own.
  2. 02FetchesEverything for exactly those dates, not a fetched window that ignores them.
  3. 03ComparesThe equally long stretch immediately before it.
  4. 04ReportsThe change per line, adding back to the change in profit.

Asked of the figures

Does the whole screen move when I change the period?

Yes — the KPIs, the waterfall, the margin and the chart. It used to slice the revenue chart and nothing else, which was survivable only because the two never sat close enough together to be compared.

How Profflow reasons

06 / What it lets you do

What follows
from getting Period comparison right.

One period, one screen

Every figure on the page answers for the same dates. A headline reporting a month beside a chart reporting a week is a page that cannot be quoted.

A like-for-like comparison

Equal length, immediately before. Not a calendar month against a partial one, and not a rolling window against a fixed one.

Custom ranges

Any pair of dates, with the comparison derived from the length you chose.

Dates from local parts

Formatted from the local date rather than through UTC, so a period does not shift by a day depending on where you are.

Fixed costs spread evenly

Rent belongs to the days it covers, not to the day it left the bank. A daily P&L that dumps a monthly bill on the first is a P&L with one impossible day in it.

Change decomposed

The difference between two periods is split into the lines that made it, and they add back exactly.

07 / How the figure is kept honest

The same four rules,
on every screen.

Read-only, on every plan

Profflow observes the accounts it is connected to. It does not write an order, a price, a campaign or a payout back to any of them.

Measured stays measured

A charge read from an account is labelled measured. Anything modelled — a forecast, a projection, a filled gap — is labelled as such on the screen it appears on.

Every figure opens

Follow any number to the dated rows underneath it. A figure nobody can check is a figure nobody acts on.

You approve

The product prepares a decision and shows the evidence. Nothing consequential happens until you say so.

Questions

About Period comparison.

Why not compare to the same month last year?
Because most stores on Profflow do not have a year of history yet, and a comparison against data that does not exist is a blank. Where the history is there, a custom range does it.
What counts as the period before?
The stretch of the same length ending the day before yours starts. Seven days compares to the seven before it; a quarter to the quarter before it.
Does a partial month compare fairly?
It compares to an equally partial stretch, so eight days compare to eight days rather than to a full month that would always look bigger.
Can I compare two arbitrary ranges?
You choose the period; the comparison is the stretch before it. Two unrelated ranges against each other is a report, and that is what the export is for.

One operating system

Each part is useful on its own. Profflow holds them in one model, so a figure here carries the context from everywhere else.

See the whole product

See Period comparison on your own figures.

A period is a pair of dates, everything on the screen is fetched for it, and the comparison is the equally long stretch immediately before. A week against the month before it is not a change — it is two different questions.