13-week cash flow forecast guide, with a worked example
How to build a 13-week cash flow forecast in a spreadsheet, with receipts, disbursements, a revolver line, weekly variance analysis and common pitfalls.
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Worked examples and plain explanations: spreadsheet formats, financial models, engineering calculations and the public data behind the datasets.
FinanceEngineeringBudgetingOpen dataSpreadsheet skillsArchitectureFormats
Finance
DCF valuation in a spreadsheet, step by step with a worked example
Build a DCF valuation in a spreadsheet with free cash flow, WACC, terminal value, mid-year discounting, an equity bridge and a sensitivity table.
Loan amortization in a spreadsheet with PMT, IPMT and PPMT
Calculate a fixed-rate loan payment and build the amortization schedule with PMT, IPMT and PPMT, including sign rules, extra payments and the final payment.
Engineering
Calculating beam deflection in a spreadsheet, with a worked example
Calculate beam deflection and moment in a spreadsheet with standard formulas, consistent units, superposition, a worked steel example and the L/360 limit.
Worst case vs RSS tolerance stack-up in a spreadsheet
Set up a one-dimensional tolerance stack-up in a spreadsheet, with loop signs, mean-and-tolerance conversion, worst case and RSS compared in a worked example.
Budgeting
Debt avalanche vs snowball: months to payoff with NPER, worked
Compare the avalanche and snowball debt payoff methods month by month on three real-looking debts, and calculate months to payoff and interest with NPER.
How to build a monthly budget spreadsheet you will keep using
Build a monthly budget spreadsheet with budget vs actual columns, SUMIFS formulas, a 50/30/20 starting split, sinking funds and a month-end reconciliation.
Open data
GDP data explained: current US$, constant prices and PPP
When to use GDP in current US dollars, constant prices or PPP, why country rankings change between them, and real 2025 World Bank figures to show it.
Global freshwater withdrawals: what the World Bank data shows
World freshwater withdrawals were 3,853 billion cubic meters in 2022. The top withdrawers, sector splits, water stress and how to read FAO AQUASTAT data.
Where to find reliable public data for your spreadsheets
Public data sources worth trusting for spreadsheets, what each covers, how it is licensed, how to pull it into a sheet, check gaps and cite it properly.
Spreadsheet skills
How to open a CSV in Excel without breaking your data
Why Excel drops leading zeros, rounds long numbers, invents dates and garbles accents when it opens a CSV, and the import settings that prevent each one.
Spreadsheet model design: inputs, calculations and outputs
Rules for spreadsheets others can trust: separate inputs, calculations and outputs, one formula per row, no hard-coded numbers, units, checks and notes.
Architecture
Room and area schedules for architects, from BIM export to summary
How to build a room and area schedule that stays consistent with BIM exports, with net vs gross area, BOMA and IPMS, room numbering and summary formulas.
Writing a construction cost estimate by CSI MasterFormat division
Build a construction cost estimate by CSI MasterFormat division, with takeoff, unit costs, markups in order, AACE estimate class and cost per square foot.
Formats
XLSX, CSV, ODS, XML or Numbers: which spreadsheet format to use
How XLSX, CSV, ODS, XML Spreadsheet 2003 and Apple Numbers differ inside, what each one keeps (formulas, styles, sheets, types) and which to pick for a job.
From the same shelf
How to Remain Valuable When Intelligence Becomes Cheap
A 224-page practical book about the scarce human, economic and strategic advantages that stay valuable even when AI can do most cognitive work. Published by The Knowledge Project.
224 pages · PDF + EPUB · $3.84