Research Paper

Why Electricity Demand Differs Across Two Statistical Sources

Author	Tianhong Zhang
Summary	Chapter III of EDMC Energy Trend, published monthly by IEEJ, reviews recent trends of electricity supply and demand using statistical data. Readers may have noticed that there are two measures of ...
Outline	Two measures of electricity demand in EDMC Energy Trend showed opposite year-over-year trends in January 2026. This short paper compares their definitions and examines whether differences in reporting periods help explain the discrepancy. The analysis applies a weighted-average approximation to five years of monthly data and evaluates its fit using root mean square error (RMSE). The results suggest that meter-reading-based reporting contributes to the contrasting trends.
Keyword	Electricity demand; reporting periods; weighted-average approximation; root mean square error
Media	ＨＰ (10/6/2026)
Report PDF	https://eneken.ieej.or.jp/data/13568.pdf