Cases present each month
Fictional example: 100 cases in January and 120 in February are not 220 distinct cases. The same cases may appear at both dates.
In-depth practical guides
Distinguish stocks, flows and cumulative totals
Choose the correct time basis before adding values or comparing periods.
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AI-generated illustration · Reports and charts on a data review desk. Illustrative scene with no real data.
Does the number describe a position or events over a period?
A stock describes a position at a date; a flow describes events over an interval. A cumulative total adds flows from a stated origin. Confusion can count one reality repeatedly or turn a snapshot into a trend.
Read definitions
Record unit, reference date, interval and scope. Cases open on 31 March differ from cases opened during March. The chart title alone is insufficient.
Choose aggregation
Add flows across compatible, non-overlapping periods. Do not sum monthly stocks to obtain an annual stock. Averaging stocks requires stated dates, frequency and weights.
Explain changes
Compare closing and opening stocks with inflows, outflows and adjustments. Reclassification, correction or scope changes may explain differences without new events.
Document cumulative totals
State starting point, reset rules and revisions. Subtract totals to derive a flow only when definition and scope are stable and revisions do not distort the difference.
Situations and decisions
Typical situations for preparing a check. They do not describe completed assignments or actual observations.
A cumulative total falls
Illustrative case: a published total changes from 300 to 290 after correction. Do not automatically announce −10 events. Find the revision and retain versions.
Record to retain
- Stock, flow or cumulative definition
- Exact dates and intervals
- Inflows, outflows and adjustments
- Aggregation and versions
Official references
Related source profiles
Related protocols
Checks before reaching a conclusion
- Is time reference explicit?
- Do intervals overlap?
- Are adjustments known?
- Does the cumulative origin stay fixed?
A series with explicit time objects and defensible aggregation rules.
Frequently asked questions
Can twelve monthly stocks be summed?
The sum is not an annual stock. It may measure cumulative exposure in a defined setting with a particular unit, which must be named and justified.
Can a cumulative total decrease?
Yes, through corrections, reclassification or scope changes. Read version notes before interpreting it as negative events.
TOOLS / REGISTERS
Write a record
Reconciling opening stock, flows and closing stock requires consistent scope and adjustments. A chart alone cannot reconstruct the series.
- Access date and time zone
- Exact URL
- Stock reference date
- Flow interval / cumulative origin
- Metric / measurement
- Dimensions / filters
- Method / definition
- Limit / uncertainty
- Decision / next action
- Review owner
- Next review