Supplementary Material S1: Reproducible cost and market model for the Hejaz rail corridor's missing link

Reproducible cost and market model supporting the article "Reviving Endowment Finance for Railways: Waqf, Advance Sales and the Funding of the Hejaz Corridor's Missing Link". The workbook contains every input, its source and every calculation used in the paper, as live formulas. Any assumption can be changed and the model recomputed. Contents:- Assumptions: unit costs, scenario levers and the exchange rate, each with its source and the caveat attaching to it.- Geometry: section lengths for the corridor, derived from published settlement coordinates by great-circle distance and a circuity factor calibrated on two existing railways.- Cost: capital cost of the missing link and the proposed Ha'il-Madinah extension, with AACE estimate class and reference-class uplift.- Demand: overland pilgrim arrivals from the Saudi General Authority for Statistics Hajj and Umrah bulletins, converted to rail journeys.- Presale: the advance-purchase instrument sized against the published external Umrah population.- Engineering: the author's own engineering estimate for the proposed alignment, and its comparison with the published-source estimate on a common scope.- Sources: every source used, with URL. Scope note: the workbook contains no operating cost, tariff, revenue, subsidy requirement or benefit-cost analysis. It is a capital cost and market estimate, not an economic appraisal. Known weaknesses are listed on the README sheet and in Section 7.3 of the article.