April 2026 Forecast Accuracy Report
Standing benchmark memo for trading desks, operators, and procurement teams tracking whether Gramm still justifies a switch from the feed they use today.
This issue in numbers
Publicly benchmarked market regions in the current issue.
Active forecast coverage spans day-ahead through 15-day runs.
Relative California benchmark reduction from 4.8% to 2.9% MAPE.
California remains the cleanest public signal for a side-by-side switch decision.
ERCOT still deserves more attention on the bad days than on the average day.
Day-ahead through 15-day coverage now sits on one delivery surface.
Territory benchmark snapshot
California is still the easiest place to start
The California day-ahead benchmark remains the simplest public read on whether Gramm is materially better than the incumbent baseline.
Read benchmark memo→In Texas, the bad days matter most
ERCOT buyers care less about average days than about the days when weather and price move together. Large misses are where load forecasting gets expensive.
Request market backtest→One API now covers tomorrow and the rest of the planning window
7-day and 15-day runs now sit on the same API surface as the short-horizon forecast, which matters for teams trying to avoid vendor handoffs.
Review API docs→