Storage Decay Ratio
Definition
Measures the growth of “Dark Data” and the effectiveness of data lifecycle policies for data cloud platforms. This KPI identifies storage costs attributed to data that has not been accessed or queried within a set window (e.g., 90 days). A higher percentage reveals a failure in data governance and lifecycle automation, indicating that the organization is paying premium prices for stagnant data, while a lower percentage indicates healthy data hygiene.
Formula, as published
Storage Decay Ratio = (Volume of Unaccessed Data / Total Data Volume) x 100
- Data sources:
- Storage usage history and catalog metadata Data lifecycle and retention policy logs Data Cloud Platform storage billing reports
Calculate it
Example values to start with; replace them with yours.
From the FinOps Foundation
More Rate Optimization KPIs
Definition and formula: Storage Decay Ratio, FinOps KPI library, FinOps Foundation, licensed CC BY 4.0, read 16 Oct 2026. Changed: HTML removed, dashes and British spellings changed, formula split from its data sources and examples. The calculator and the notes are Finitizer’s.
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