Formula-first financial guides
Practical breakdowns of the equations behind SBA loans, tax optimization, real estate underwriting, and investment math — written for business owners who want to understand the numbers.
ROI calculation methods: simple, annualized, and risk-adjusted returns
Simple ROI and annualized ROI answer different questions. This guide covers the formulas for both, a worked real estate example, benchmark comparison tables, and the most common variable mistakes that distort investment return calculations.
Profit margin formula: gross, operating, and net margin calculations
Gross margin, operating margin, and net margin are three mathematically distinct metrics that each measure a different layer of the income statement. This guide covers the formulas, a worked example, and industry benchmark ranges.
SBA loan amortization explained: how monthly payments are calculated
A step-by-step breakdown of the standard amortization formula that determines every SBA 7(a) loan payment, with worked examples using 2026 Prime Rate figures.
S Corp tax savings breakdown: the self-employment tax equation
How the S Corp election reduces self-employment tax liability through the reasonable salary and distribution split — with the exact FICA formulas behind the savings.
DSCR for real estate investment: what lenders calculate and why it matters
The debt service coverage ratio is the primary underwriting metric for investment property loans. This guide covers the formula, benchmark ranges, and how income and expenses shift the number.
Compound interest and long-term growth: the mathematics of exponential returns
Compound interest is the most fundamental concept in investment math. This breakdown covers the compound interest formula, the rule of 72, and how compounding frequency affects total accumulation.
Section 179 deduction and equipment cost modeling for business owners
The Section 179 deduction allows businesses to expense qualifying equipment in the year of purchase rather than depreciating it. This guide covers the 2026 limits, phase-out thresholds, and the tax savings formula.