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Case study 02 · Board-facing BI

One site accounted for all of a nine-site portfolio's net decline

Nine sites modelled into a governed mart layer for a board deciding where to put its capital. Every claim was checked against all nine before it reached a slide: the checks killed one claim outright and cut a headline figure from 3x to 2.25x.

Role
Solo data modelling + BI build
Sites modelled
9, across 5 regions
Tool
Tableau
Audience
CEO / Board

1The problem

Devon Corporation's retirement-living locations each had their own reporting, no standard definitions, and no view of the portfolio as a whole. The brief: build the first portfolio-level executive dashboard, something a board could read in 30 seconds and walk away from with a specific place to focus attention and capital, not a data dump.

2The approach

The source tables had different grains and didn't reconcile with each other by design, so flattening them into one join would have quietly fabricated relationships that weren't real. Instead, the source tabs went through staging → intermediate → marts, each mart answering one question at one grain, connected in Tableau via relationships rather than physical joins.

Data lineage diagram: five layers from source workbook tabs through staging, intermediate, marts, to the six board-facing dashboard views.
Source → staging → intermediate → marts → dashboard. Every number on the dashboard traces back to a source tab. Scroll the diagram sideways to read it all.

One site accounting for the whole net decline is arithmetic rather than inference: occupied units fell 15 across the portfolio and 15 at that one site, with every other site netting to zero, and it holds on gross declines too (that site is 65% of them). Elsewhere, where a pattern could have been asserted from a trend line, I tested instead: a control chart, a trend regression and an ANOVA all said turnaround was stable, killing a draft claim that it was drifting worse. Which site you are in explains 33.8% of the variance in turnaround; which quarter it is explains 1.8%. I adopted a standing rule partway through: before any claim goes on a slide, check it against all nine sites and for materiality. That rule caught, among others, a "3x the next site" figure that was actually 2.25x once checked properly.

Rejected hypothesis, kept anyway An early read blamed the decline on falling satisfaction scores. Checking the timeline showed occupancy had already turned down a full quarter before the satisfaction drop: the causal story didn't hold, so it was cut. A test you ran and dropped is stronger evidence of rigour than a clean narrative, so it's documented rather than hidden.

3The outcome

100%

of the portfolio's net occupancy decline traced to a single site.

36%of the portfolio's $43.6M unsold value, at that one site
1.5 → 9.1ppthe site's occupancy gap to the portfolio, widening across three years

That site sat at 83.9% occupancy against a portfolio average of 93.0%, with the next-worst site at 91.1%. And it isn't a size effect: per unit it holds $105.6k of unsold value against $64.0k at the next site, 1.65x the runner-up after adjusting for scale. The dashboard's visual grammar does one job: neutral everywhere, with a single emphasis colour reserved for the hero numbers and the one site that needed attention. The emphasis colour doesn't decorate. It points.

The recommendation was four actions, in order, each with an owner.

Gross opportunity, not a forecast: it assumes the units sell, and excludes refurbishment, marketing and incentives.

Devon Corporation portfolio scorecard: 93.0% portfolio occupancy down 0.8pp, $43.6M unrealised value in vacant units, an occupancy-versus-value scatter isolating Lavender Town, turnaround days by location, and entry versus resale price trends.
Static export of the dashboard. Open the interactive dashboard on Tableau Public →

4The limits

Three things this analysis can't answer. There is no target or industry benchmark anywhere in the data, so nothing here says whether 93% occupancy is good or bad, only that it fell. There is no sales lead-time data beyond turnaround, so the honest answer to "how long would a fix take" is that site's 134 days and nothing better. And the move-in and move-out counts don't reconcile with the occupancy balance, which is a data-quality problem to raise at source with agreed definitions rather than paper over downstream.

Those are the questions I'd open with, not close with.

TableauDimensional modelling SQLStatistical testing (ANOVA, regression) Data governanceExecutive storytelling
About this work A work sample, not a client deliverable. Devon Corporation and the location names are fictionalised and the underlying figures synthetic; the modelling approach, the statistical method and the findings process are exactly what I did.