Add HDD Storage Price Index to Economic Data (commodity price series)

[AdamDudley]

Adds an open, downloadable commodity price time series to the Economic Data → Other economic data and indicators section, alongside the existing Oil, Natural Gas and Gold price series.

Dataset

HDD Storage Price Index — https://github.com/AdamDudley/hddhunt-price-index

Daily cheapest and median price-per-TB (USD/TB) for new internal 3.5" SATA hard drives by capacity tier on Amazon US, published as a growing daily time series (started 2026-08-17).

Meets the awesome-data quality bar

• Directly downloadable, no login / no paywall: immutable dated CSV/JSON snapshots plus a rolling CSV and JSONL time series.
• Open licence: CC BY 4.0 (LICENSE + CITATION.cff + .zenodo.json in-repo).
• Documented methodology in the README, with an honest caveat that these are asking/listing prices, not transactions, and are Amazon-US-only.

This mirrors the format of the recently-merged external asking-price entry in property-prices.md (Phuket Condo Asking-Price Snapshot, #443). Happy to adjust placement or wording if you'd prefer it elsewhere.