BUSINESS OPTIMISM–PESSIMISM (BCI) AND SOLAR ACTIVITY (1974–2026): SUPERPOSED EPOCH ANALYSIS (R = 0.986)

Abstract: Subject of research: This study examines the causal relationship between solar activity cycles and the OECD Business Confidence Index (BCI) cycles for the period 1974–2026.

Methodology: The author builds upon the methodological approaches of W. S. Jevons and A. L. Chizhevsky by applying the "superposed epoch analysis" (method of superimposed epochs) to investigate the links between solar activity and the OECD Business Confidence Index (BCI).

Key results:

1. Statistical significance: In the plot of the average Business Confidence Index (BCI) versus the year’s ordinal position within the solar activity cycle, the coefficient of determination ($R^2$) is 0.9712 (based on 53 years of observations). The multiple correlation coefficient ($R$) is 0.9855.

2. Optimism (BCI > 100) occurs within the range of moderate solar (geomagnetic) activity.

3. Pessimism (BCI < 100) occurs during extremes of solar (geomagnetic) activity.

4. Forecast: The projected BCI value for 2026 is 99.79, and for 2027, it is 100.63.

Keywords: solar activity, Wolf numbers, geomagnetic activity, business confidence index, BCI, pessimism, optimism, economic cycle, forecasting, A.L. Chizhevsky.