How we compute the Texas Rate Index
Every number on the Texas Rate Index is derived from live Power to Choose listings. Our formula is public, our data refreshes nightly, and every figure is independently verifiable. Here's exactly how we do it.
The data source
We pull the full plan list from powertochoose.org nightly via our public plan scraper. For each plan we capture the provider, plan name, TDU territory, rate type, contract term, and the three standardized disclosure rates (500 kWh, 1000 kWh, 2000 kWh) from the Electricity Facts Label. We do not mix in third-party data — 100% of the index comes from PTC.
The formula
For each TDU territory, the daily average is the arithmetic mean of the 1000 kWh disclosure rate across every eligible fixed-rate plan. The statewide headline number is a plan-weighted mean (not a TDU-weighted mean) — a TDU with 500 plans contributes more to the average than a TDU with 50 plans, because it more accurately reflects what the typical Texas customer is actually seeing when they shop.
Refresh frequency
The refresh-plans cron runs nightly at 08:00 UTC (03:00 Central). The index is computed immediately after the plan refresh completes, so the number on /rate-index is always based on the freshest data we have. Stale indexes are never shown — if the cron fails, the page displays the last successful snapshot and labels the date.
What we exclude
We exclude variable-rate plans, indexed plans, prepaid plans, time-of-use plans, and plans with a disclosed bill credit or minimum usage penalty. The rationale: those plans have pricing that can swing wildly month-to-month and including them would pollute the average. The index reflects the fixed-rate market only — which is what 90% of Texas residential customers actually buy.
Known limitations
The index does not account for regional delivery fee variations, TDU surcharges, or individual customer usage patterns. It is a HEADLINE number, not a personalized recommendation. For a number tailored to your actual kWh usage, upload your bill on the Voltcheckr home page — we'll compute a per-customer effective rate that factors in delivery fees and tiered pricing.
How to cite it
Cite the index as: "Voltcheckr Texas Rate Index, computed from Power to Choose listings." Include the snapshot date so readers can reproduce your figure. The index is free to reference in any article, blog post, or embed, commercial or not. Attribution is required.