Download the CASTR Spreadsheet
CASTR Spreadsheet 75.7.0-Release.xlsm — macro-enabled Excel workbook (.xlsm)
CASTR Spreadsheet runs a Monte Carlo cost and schedule risk simulation entirely inside Excel. You document the project, structure the estimate, enter base uncertainty and a quantified risk register, then run the simulation to get confidence-based (P-level) budgets, contingency by source, year-of-expenditure conversion, sensitivity and tornado analysis, tail drivers, what-if testing and a joint cost–schedule confidence chart. It follows the same FHWA NHI Course 134205 methodology as the CASTR application. How the two differ.
Try the example project
Download the spreadsheet with a seven-risk highway project already loaded and run, or import its inputs into your own copy. It shows dependency, correlation, predecessor links and schedule-driven cost, explains how to read every results sheet, and lists the exact results to check your run against.
Pricing
| Item | Price |
|---|---|
| CASTR Spreadsheet — this workbook, every version | Free |
| CASTR application — perpetual license | Free |
| CASTR application — 12 more months of updates (optional) | $49.99 |
The CASTR Spreadsheet needs no license key and has no upgrade coverage: every new version is a free download from this page. The license and the $49.99 renewal are for the CASTR application only (application pricing).
Requirements & Notes
- Microsoft Excel for Windows (desktop) with macros enabled. Works with both 32-bit and 64-bit Excel.
- Not compatible with the Bluebeam Excel add-in while it is active — disable it before opening.
- Use only one active CASTR workbook at a time.
- Run the tool directly from the worksheets or from the CASTR add-in menu and Switchboard.
- Color coding on the About sheet identifies user inputs, CASTR outputs, calculated values, QC checks and errors.
Want to run simulations on your own model?
Check out SimuXL.com — Monte Carlo simulation inside Excel, for any workbook.
Getting Started
- Download the workbook using the button above and save it to a local folder (not a network or cloud-synced location the first time you open it).
- Unblock the file. Windows marks files downloaded from the internet and Excel will silently disable their macros. Right-click the .xlsm file → Properties → check Unblock → OK.
- Open in Excel and click Enable Content when prompted, then read and accept the Disclaimer sheet.
- Work the sheets in order — Home → Names → Inflation → Structured Estimate → Base Uncertainty → Risk Identification → Risk Register → Simulation Settings — then run the simulation and review the results sheets.
- Learn more: the User Manual and the Video Library were written for the CASTR application. They explain the same method and workflow, but the screens are the application’s, not the workbook’s. To see every feature at work on a small project, load the example project.
Input Sheets
Home
Project information, review dates, team roles, project complexity and the AASHTO sliding-scale contingency range for your % design completion.
Names
Define project segments, phases (PE, RW, CN, UT, etc.), inflation-table assignments and risk categories.
Inflation
Compound inflation tables by phase with cumulative year/month factors used for year-of-expenditure (YOE) conversion.
Structured Estimate
Roll the sponsor's estimate into cost phases: base cost, traditional contingency, prior and fixed costs, inflation point and dates.
Base Uncertainty
Base variability and market-condition ranges by phase-segment, plus the schedule duration analysis that feeds the simulation.
Adjustments
Track pre-review vs. post-review estimate changes line by line with an audited net-adjustment total.
Risk Identification
Workshop capture sheet: category, phase-segment impacted, description, response, dependency and probability. Syncs to the register.
Risk Register
Quantified cost and schedule impacts (min / most likely / max), risk status, dependencies and parent/prerequisite probability logic.
Minor Risks
Aggregate small risks below a mean-value threshold so they are carried without cluttering the register.
Predecessor Links
Phase-segment predecessor/successor links with lag so schedule delays propagate downstream.
Correlation
Rank-correlation editor for one-to-many pairs with automatic matrix validity (positive-definite) checking.
Simulation Settings
Toggle base variability, market conditions and the register; set iterations, random seed, convergence monitoring, percentiles and budget confidence.
Results & Analysis Sheets
Year of Expenditure
Base cost, register cost and delay by phase-segment in current-year and YOE dollars, with confidence-based budgets.
Summary
P-level total project cost, contingency in $ and %, P10/P90 spread, COV, and a check against the national contingency range.
Scenarios
Layered results: base cost + base variability, + market conditions, + risk register, in CY and YOE, with contingency by source.
Distributions & Histogram
PDF/CDF bins for every output, plus a presentation-ready results chart.
Sensitivity
Spearman rank correlation, variance share and top-driver share for each output.
Tornado
Tornado charts of the top risk drivers, selectable by output.
Risk Rank
Cost and schedule threats and opportunities ranked by expected value.
Tail Drivers
Which risks fire in the favorable (lower 10%) and adverse (upper 10%) tails, with excess contribution.
What-If Sensitivity
Deactivate risks one at a time and watch live contingency and P-level cost respond.
Joint Confidence
YOE cost vs. completion-date scatter with 80/90% contours, marginal P-levels and joint coverage.
User-Defined Outputs
Add any cell or formula as a tracked simulation output and it appears in every results sheet.
CASTR Spreadsheet or the CASTR application?
CASTR comes in two editions. Both follow the same method; they differ in how you work and what they cost to keep up to date.
| CASTR application | CASTR Spreadsheet | |
|---|---|---|
| What it is | A Windows program (CASTR.exe) that runs on your computer and opens in your web browser | A macro-enabled Excel workbook (.xlsm) |
| You need | Windows; Chrome, Edge or Firefox | Microsoft Excel for Windows (desktop, 32- or 64-bit) with macros enabled |
| Price | Free perpetual license with 12 months of updates; after that, updates are optional at $49.99 for another 12 months | Free. No license key and no renewals: every new version is free |
| Version numbers | 2.x | 75.x |
| Method | FHWA NHI Course 134205 | The same |
| Extras | Guided workflow, project management, starter risk library, triage scoring and diagnostics | Everything on worksheets you can open and inspect; an example project with known results |
| Inputs files (.pri) | Imports the Spreadsheet’s .pri files | Saves and imports .pri files |
| Release notes | What’s New | The ChangeLog sheet in the workbook |
| Help | User Manual and Video Library | This page and the example project. The User Manual and videos explain the same method on the application’s screens |
| Download | CASTR.zip | The button at the top of this page |