Signal · Quality

Know when a change is real, in plain words

Every week the number moves, and someone asks why. Most of those moves are noise. A few are real, and those are the ones to act on. Statistical process control (SPC) separates the two with a centre line, control limits and a handful of rules. Power BI has no SPC chart, the ones on AppSource are written for statisticians, and board packs that show twenty measures as SPC summaries are still built by hand.

Free to use, with no watermark and no time limit. Pro from $3 per viewer a year.

Deliveries got faster from late MayDays from order to delivery, weekly; lower is better
Upper 4.8Mean 4.0Lower 3.3Above the upper limit, 2 MarImproving12 weeks below the mean since 25 May
Light report
Deliveries got faster from late MayDays from order to delivery, weekly; lower is better
Upper 4.8Mean 4.0Lower 3.3Above the upper limit, 2 MarImproving12 weeks below the mean since 25 May
Dark report

What it shows

Signal draws your measure over time with its mean and its upper and lower limits, then checks the four standard rules. Points that break a rule are fjord blue when the change is good and ember orange when it is bad, because you tell Signal whether higher or lower is better. Next to the points it writes what it found, such as “Above the upper limit, 2 Mar” or “14 weeks below the mean since 25 May”. At the top it gives a verdict for the latest point (Improving, Concern or No signal) and, with a target, whether the process will meet it.

  • A point outside the limits.
  • A shift: 7 points in a row on one side of the mean.
  • A trend: 6 points in a row rising or falling.
  • Two of three points close to a limit.

How to set it up

Add Signal from AppSource or the .pbiviz file, then drag in:

Axis
A date or period, such as week or month.
Values
The measure, such as days from order to delivery or on-time orders.
Denominator
Optional: what the value is divided by, such as orders, for rates like errors per 1,000 orders.
Target
Optional: a target measure, drawn as a dotted line.
PhasePro
A column that names each period, such as “Old picking route” and “New picking route”. The limits are recalculated where it changes.
Split byPro
One row on the board per warehouse, ward or team.

Read the full Signal guide

In the report

  • Hover a point for its value, the mean, the limits, the target and the signal it is part of.
  • Click a point to filter the report to that period, or a board row to filter it to that item; the rest dims.
  • Light or dark background, high-contrast mode, and your own colours.
  • Tab into the chart and move between points with the arrow keys; screen readers hear each point’s date, value and signal.
  • The format pane, the labels and the messages are in English and Norwegian.

Free and Pro

FeatureFreePro
XmR and run charts with mean or median and control limits✓✓
The four rules, coloured by whether higher or lower is better✓✓
Plain-language signal labels, verdict, target line and target assurance✓✓
Rates on an XmR chart (value ÷ denominator, per 1,000)✓✓
Tooltips, click to filter, keyboard, high contrast, light and dark✓✓
Phases: limits recalculated after a change—✓
p′ and u′ charts for shares and rates, with Laney’s adjustment—✓
Board view: several measures, or one row per item, each with a mini chart, verdict and target—✓

Free features always work, with no key and no tag. Pro features need a licence key for Signal or Everything. Without a valid key, Signal draws the first measure as one XmR chart with one set of limits, with a short notice and a “Try Pro free” button. A paid key keeps Pro working for 7 days after it runs out, so a late renewal never breaks a report.

Your data stays in your report

Signal makes no network calls and stores nothing outside the report. The licence key is checked inside the visual, so it also works offline, in Report Server and in locked-down tenants.

How the visuals handle data

Pro licence
$36per creator a year
$3per viewer a year

For Signal alone. The entire suite is $90 per creator and $7.50 per viewer, or license the whole organisation.

See pricing

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