CharterCostTracker

A Python system for estimating charter transfers’ effects on district revenue, covering 1,023 Texas districts over five years.

Published in
Texas AFT
Date
June 2024
Topic
Data engineering, school finance, charter transfers, automated reporting
Publication
Read the published article

I built CharterCostTracker to collect Texas education data, estimate how charter transfers affect district revenue, and generate reports for Texas AFT and public education advocates. I handled all the programming and engineering, expanding a manual district-by-district process into a five-year dataset covering 1,023 districts.

The project began with constituent concerns about a proposed charter campus while I was a legislative director. A longtime advocate and mentor had developed an estimation method and statement-of-impact template with school finance experts. I translated that method into code and reviewed the calculations with her as we expanded the analysis statewide.

Data and calculations

I collected TEA directory, enrollment, transfer, finance, accountability, and recapture records. Selenium scripts located reports in TEA’s interactive report builder; an asynchronous downloader retrieved them with retries and checks for missing or incomplete files. I retained source URLs, report dates, run IDs, and payment cycles.

The parsers handle changing spreadsheet layouts, restore leading zeros in district IDs, and reconcile district and charter names. The calculations combine transfer counts with funding, attendance, and enrollment data, accounting for changes in formulas and report formats across years.

The reports keep observed transfers separate from estimates for masked counts. One later scenario assumes five transfers per receiving charter entity with a masked count and reports that estimate separately.

Reports and publication

I automated statewide spreadsheets, district breakdowns, Word and PDF reports, maps, and charts. I also generated responsive HTML tables linking to district reports for Texas AFT’s website.

I wrote the entire June 27, 2024 Texas AFT article, “The Growing Financial Strain of Charter School Expansion on Texas Public Schools”, presenting the findings and their implications. The link opens an archived copy because the original URL is no longer available.

I continue to prepare analyses for hearings, town halls, and discussions about school closures and budget cuts. This work also supported research for Our Schools, Our Democracy and informed the data-collection tools in Data for Public Education.

Browse the statewide and longitudinal datasets.

Original district deliverable · May 2024 inputs

From state records to an Austin ISD report

I built the collection and reporting pipeline, generated district summaries, and wrote the Texas AFT newsletter article explaining the findings. This is the original Austin ISD Word report from the project repository.

  1. Collect and match. Join TEA transfer reports, enrollment counts, and Summary of Finances records by district and school year.
  2. Estimate. Calculate selected formula revenue per refined average daily attendance, then apply the district’s attendance-to-enrollment ratio and observed charter-transfer count. Masked transfer counts are excluded from this version.
  3. Deliver. Generate a district report with five years of counts, estimates, and source notes, plus a web index for finding each district’s document.
2023–24 observed transfers
12,636
District enrollment
72,830
Transfers ÷ enrollment
17.35%

The report estimated $624,927,517 in cumulative revenue losses over 2019–20 through 2023–24. That is a model estimate, not an audited accounting of dollars transferred. Its 2023–24 finance inputs were preliminary, accessed May 19, 2024.

Original Austin ISD report (Word)Calculation codeReport generator

The explorer below uses a later, June 21 export for one school year. Its figures can differ from this original five-year report.

2023–24 · June 21, 2024 export

From source inputs to an estimate

Choose a district to inspect the reported funding, attendance, enrollment, and charter-transfer inputs alongside the published revenue estimate.

1020 matching districts. Showing AUSTIN ISD.

AUSTIN ISD

Estimated revenue effect
$101,010,915
Charter transfers
12,636
District enrollment
72,830

More columns: scroll the table horizontally.

Estimated district revenue$582,195,706
Refined average daily attendance63,407.35
Summary of Finances05-10-2024 (Run ID: 43118, Preliminary)

The model estimates revenue associated with charter transfers using the district’s funding and attendance inputs. It does not measure recoverable savings or promise that every estimated dollar would return if a student transferred back.

Values are reproduced from the source export, including masked enrollment counts such as “<10”. This one-year exhibit contains 1,020 district rows; the full project covers 1,023 districts across five years.

Austin ISD workbook excerpt (PDF)Download the exhibit dataOriginal generated report indexCode and source exports