Research Article
Effect of Ap-Index of Geomagnetic Activity on S&P 500 Stock Market Return
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 |  | ā | Mean | Std.Dev | Maximum | Minimum | Observations |  | 
 |  |  | 10.76 | 5.23 | 35.00 | 2.00 | 240 |  |  | 1414.73 | 417.95 | 2673.61 | 735.09 | 240 |  |  | 1452.19 | 413.33 | 2694.97 | 832.98 | 240 |  |  | 1360.93 | 414.20 | 2605.52 | 666.79 | 240 |  |  | 5.90 | 3.21 | 16.20 | 1.15 | 240 |  |  | 22.63 | 20.49 | 109.15 | 4.2 | 240 |  | 
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