Reconstruct a Historical SIRAS Population Estimate
Last updated: Nov 05, 2026
Historical Population Estimate
Use this fallback when a timely local SIRAS data-export snapshot from the needed time frame does not exist. The methods below estimate an earlier population from archived SIRAS history.
To reduce the need for reconstruction later, each SIRAS LEA should preserve timely local point-in-time exports on a recurring schedule, such as monthly. See Census Day Search and Store: Preserve a Point-in-Time SIRAS Snapshot.
Use this fallback when a timely local SIRAS data-export snapshot from the needed time frame does not exist. The methods below estimate an earlier population from archived SIRAS history.
To reduce the need for reconstruction later, each SIRAS LEA should preserve timely local point-in-time exports on a recurring schedule, such as monthly. See Census Day Search and Store: Preserve a Point-in-Time SIRAS Snapshot.
You are here: Reconcile & Repeat → reconstruct a missed historical population.
This is an estimate, not a recovered point-in-time snapshot.
Archived SIRAS events show what was documented in archived transactions. They do not guarantee the exact Current population that appeared on an earlier date. When an actual same-date snapshot exists, use that snapshot instead.
Archived SIRAS events show what was documented in archived transactions. They do not guarantee the exact Current population that appeared on an earlier date. When an actual same-date snapshot exists, use that snapshot instead.
Choose the Right Historical Workflow
| I missed a Census/EOY population and need an estimateUse the predefined CALPADS Historical Estimates as the starting candidate population. | Reconcile SIRAS records to SENR recordsUse SIRAS and SIS/CALPADS data sources to understand the population crossover and reconciliation methods. |
| I need to build a custom historical/archive queryArticle 100 owns Historical/Advanced query construction and archive-vs-Current comparisons. | I only need one student's historical recordUse the individual-record procedure instead of reconstructing a population. |
| I already have the population and want to analyze itArticle 750 owns Found Set → Statistical Report / Data Export analysis. | I need to preserve a future point-in-time snapshotCapture the actual Current population on the date instead of reconstructing it later. |
SIRAS path for this fallback: Search → Predefined Queries → CALPADS Historical Estimates
On This Page
Build the Quick Historical Candidate Population
- Select Search → Predefined Queries.
- Open CALPADS Historical Estimates.
- Select the academic year you need.
- Understand the predefined population: Fall includes applicable Active and Pending records from July 1 through Fall Census Day. EOY includes applicable Active and Inactive records for the July 1–June 30 academic year being reconstructed.
- Select Search to List.
- Review the returned archived records before treating the result as a student population.
SIRAS predefined historical population queries already apply the appropriate Most Recent Archive logic.
That helps keep the candidate Found Set to no more than one qualifying archive result per student. If the predefined estimate does not fit the date/population question and you need to build the historical query yourself, move to Advanced Historical Queries for Archived Student Data.
That helps keep the candidate Found Set to no more than one qualifying archive result per student. If the predefined estimate does not fit the date/population question and you need to build the historical query yourself, move to Advanced Historical Queries for Archived Student Data.
CALPADS Historical Estimates provide a quick starting candidate population from archived SIRAS records.
The result is a historical archive candidate set, not a recovered same-date Current snapshot.
Why the Archive Set Is Only an Estimate
Querying archived records can over-count or under-count students when the goal is a historical head count because:
- one student may have several archived events during the year;
- another student may have no new archived meeting/reporting event during the period even though the student was enrolled;
- SIRAS is not always the system of record for historical district enrollment; and
- a later Current record may no longer be at the same district or may have changed designation.
Treat the SIRAS archive result as a candidate population.
The reconstruction becomes more useful when it is reconciled against enrollment evidence from the same time frame.
The reconstruction becomes more useful when it is reconciled against enrollment evidence from the same time frame.
Improve the Estimate with Same-Timeframe Enrollment Evidence
For a more defensible historical population estimate, compare the SIRAS archive candidate set with the best available list of students enrolled during the same academic year or measurement date.
- Obtain the same-timeframe SENR enrollment population from the district's enrollment source or applicable CALPADS enrollment report.
- Build the SIRAS historical candidate population for the same year/date.
- Export the SIRAS candidate population.
- Compare the two populations by SSID.
- Investigate students found only on one side instead of deleting them from the working set automatically.
- Use the verified enrollment/participation timeline to decide whether each candidate belongs in the reconstructed population.
For two-file comparison mechanics, use SIRAS vs. CALPADS Bulk Extract Reconciliation.
When Reconstructing Multiple Academic Years
- Use Reset Search between academic years so records from the prior query do not contaminate the next Found Set.
- Run one academic year at a time.
- Export each year to its own file.
- Put the academic year in the filename.
- Preserve the query/date criteria used for that file.
- Compare each year's SIRAS candidate set with the corresponding same-timeframe enrollment population.
Prepare the Candidate Population for Comparison
Once the predefined historical estimate returns the candidate population:
- Verify the Found Set is the year/date/population you intended.
- Use Tools → Data Export when you need student-level rows for reconciliation.
- Include the identifiers/fields needed for the comparison and use a filename that identifies the academic year/date and purpose.
- Keep the SIRAS archive candidate file separate from the same-timeframe SENR/CALPADS enrollment source so the two sources can be compared explicitly.
For general export mechanics, use Data Export Help. For generic Found Set → report/export analysis after the population is established, use Analyze a Current or Historical Student Population.
What to Do with the Reconstructed Estimate
| Next question | Go to |
|---|---|
| I need counts, percentages, grouped summaries, or a general export from this Found Set. | Analyze a Current or Historical Student Population |
| I need to compare the SIRAS candidate set with CALPADS/SENR rows. | SIRAS vs. CALPADS Bulk Extract Reconciliation |
| I found a student/count discrepancy and need to determine what actually happened. | Data Monitoring Help: Investigate a Questionable Record |
| I need custom archive criteria not handled by the predefined estimate. | Advanced Historical Queries for Archived Student Data |
| I want to avoid reconstruction next time. | Census Day Search and Store: Preserve a Point-in-Time SIRAS Snapshot |
Do not present the reconstructed SIRAS count as an official certified CALPADS count unless the source actually supports that conclusion.
Document which records were included/excluded and why, and preserve the source files and criteria used for the reconstruction.
Document which records were included/excluded and why, and preserve the source files and criteria used for the reconstruction.
