Statistics of sunspot activity
September, 1997
Visual indices of solar activity by National Geophysical Data Center
| Date | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | Average | % |
| W | 71.25 | 63.25 | 50.33 | 44.00 | 67.67 | 72.75 | 75.75 | 94.75 | 94.25 | 103.50 | 94.75 | 94.00 | 84.00 | 70.75 | 61.00 | 61.75 | 51.33 | 31.25 | 16.75 | 14.50 | 27.00 | 44.25 | 41.00 | 48.00 | 50.75 | 40.25 | 30.00 | 25.25 | 17.75 | 22.00 | 55.46 | 100 |
| Wn | 71.25 | 63.25 | 41.00 | 27.00 | 47.33 | 47.00 | 36.50 | 40.50 | 35.75 | 39.50 | 38.75 | 31.00 | 39.25 | 36.50 | 42.75 | 47.75 | 39.00 | 19.25 | 16.75 | 14.50 | 15.67 | 12.75 | 3.67 | 0.00 | 0.00 | 0.00 | 4.33 | 3.00 | 3.00 | 0.00 | 27.23 | 49.10 |
| Ws | 0.00 | 0.00 | 9.33 | 17.00 | 20.33 | 25.75 | 39.25 | 54.25 | 58.50 | 64.00 | 56.00 | 63.00 | 44.75 | 34.25 | 18.25 | 14.00 | 12.33 | 12.00 | 0.00 | 0.00 | 11.33 | 31.50 | 37.33 | 48.00 | 50.75 | 40.25 | 25.67 | 22.25 | 14.75 | 22.00 | 28.23 | 50.90 |
| n | 3.75 | 3.75 | 2.67 | 3.00 | 4.33 | 4.75 | 4.25 | 4.00 | 3.75 | 3.50 | 3.75 | 3.00 | 4.00 | 3.75 | 3.00 | 3.00 | 3.00 | 2.00 | 1.00 | 1.00 | 2.00 | 3.00 | 2.33 | 2.00 | 2.00 | 2.00 | 1.67 | 1.25 | 1.25 | 1.75 | 2.82 | 100 |
| A | 1.75 | 2.00 | 1.00 | 1.00 | 1.00 | 1.75 | 0.50 | 0.00 | 0.00 | 0.25 | 0.50 | 0.00 | 0.00 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.50 | 0.33 | 0.00 | 0.00 | 0.50 | 0.67 | 0.25 | 0.25 | 0.00 | 0.42 | 14.79 |
| B | 0.00 | 0.25 | 0.00 | 0.00 | 1.67 | 0.25 | 0.25 | 0.25 | 1.00 | 0.25 | 0.25 | 0.00 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.33 | 0.00 | 0.00 | 0.00 | 0.75 | 0.50 | 0.00 | 0.00 | 0.00 | 0.00 | 0.20 | 7.10 |
| C | 0.00 | 0.00 | 0.67 | 0.33 | 0.00 | 0.75 | 0.25 | 1.25 | 0.00 | 0.00 | 0.25 | 0.00 | 0.50 | 0.75 | 0.25 | 0.00 | 1.00 | 1.00 | 0.50 | 0.75 | 0.67 | 1.50 | 0.33 | 0.33 | 0.50 | 0.00 | 0.00 | 0.00 | 0.25 | 1.00 | 0.43 | 15.19 |
| D | 0.00 | 0.00 | 0.00 | 1.00 | 1.00 | 1.50 | 2.00 | 1.25 | 1.75 | 1.50 | 0.75 | 0.50 | 1.25 | 0.75 | 1.75 | 0.75 | 0.67 | 0.25 | 0.25 | 0.00 | 0.00 | 0.25 | 0.67 | 0.33 | 0.00 | 0.00 | 1.00 | 0.75 | 0.75 | 0.00 | 0.69 | 24.46 |
| E | 0.00 | 0.25 | 0.67 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.25 | 0.50 | 0.50 | 0.25 | 0.00 | 0.25 | 0.25 | 0.33 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.33 | 0.75 | 0.25 | 0.00 | 0.25 | 0.00 | 0.00 | 0.16 | 5.72 |
| F | 1.00 | 0.50 | 0.33 | 0.00 | 0.00 | 0.00 | 0.00 | 0.75 | 0.75 | 0.50 | 1.00 | 1.00 | 1.00 | 0.50 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.24 | 8.68 |
| G | 0.00 | 0.25 | 0.00 | 0.67 | 0.00 | 0.00 | 1.00 | 0.50 | 0.25 | 0.75 | 0.50 | 1.00 | 0.75 | 1.25 | 0.75 | 1.25 | 0.33 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.33 | 0.00 | 0.75 | 0.00 | 0.00 | 0.00 | 0.00 | 0.35 | 12.52 |
| H | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.50 | 0.33 | 0.50 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.04 | 1.58 |
| I | 1.00 | 0.50 | 0.00 | 0.00 | 0.67 | 0.50 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.25 | 0.00 | 0.25 | 0.33 | 0.00 | 0.25 | 0.25 | 1.00 | 0.75 | 1.00 | 0.67 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.75 | 0.28 | 9.96 |
| x | 1.75 | 2.25 | 1.00 | 1.00 | 2.67 | 2.00 | 0.75 | 0.25 | 1.00 | 0.50 | 0.75 | 0.00 | 0.25 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.33 | 0.50 | 0.33 | 0.00 | 0.75 | 1.00 | 0.67 | 0.25 | 0.25 | 0.00 | 0.62 | 21.89 |
| r | 0.50 | 0.50 | 0.33 | 0.00 | 0.00 | 0.50 | 0.25 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.67 | 0.00 | 0.00 | 0.00 | 0.00 | 0.50 | 0.00 | 0.33 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.13 | 4.54 |
| s | 1.25 | 0.75 | 1.00 | 1.67 | 0.67 | 0.75 | 1.00 | 0.75 | 0.25 | 0.50 | 0.50 | 0.50 | 1.25 | 2.00 | 0.25 | 1.25 | 0.67 | 1.00 | 0.75 | 0.75 | 1.33 | 1.00 | 0.67 | 1.00 | 0.75 | 0.75 | 0.33 | 0.00 | 0.25 | 1.00 | 0.82 | 29.09 |
| a | 0.25 | 0.00 | 0.33 | 0.33 | 0.33 | 1.25 | 1.75 | 1.25 | 0.75 | 0.50 | 0.25 | 1.00 | 1.00 | 0.00 | 2.00 | 0.75 | 1.33 | 0.25 | 0.25 | 0.25 | 0.33 | 1.00 | 1.00 | 0.67 | 0.25 | 0.25 | 0.67 | 0.50 | 0.75 | 0.50 | 0.66 | 23.37 |
| h | 0.00 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.25 | 0.25 | 0.25 | 0.00 | 0.50 | 0.50 | 0.25 | 0.50 | 0.00 | 0.25 | 0.00 | 0.50 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.25 | 0.13 | 4.73 |
| k | 0.00 | 0.00 | 0.00 | 0.00 | 0.67 | 0.25 | 0.25 | 1.25 | 1.50 | 2.00 | 1.75 | 1.00 | 1.25 | 1.00 | 0.75 | 0.75 | 0.33 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.33 | 0.00 | 0.00 | 0.00 | 0.00 | 0.50 | 0.00 | 0.00 | 0.46 | 16.37 |
| x | 2.75 | 2.50 | 1.00 | 1.00 | 1.67 | 2.25 | 0.75 | 0.00 | 0.00 | 0.25 | 0.50 | 0.00 | 0.00 | 0.50 | 0.00 | 0.75 | 0.67 | 0.50 | 0.25 | 0.25 | 1.00 | 1.25 | 1.33 | 0.67 | 0.00 | 0.50 | 0.67 | 0.25 | 0.25 | 0.75 | 0.74 | 26.33 |
| o | 0.00 | 0.50 | 0.67 | 2.00 | 2.67 | 2.50 | 2.75 | 2.50 | 2.00 | 1.75 | 1.50 | 1.50 | 2.75 | 2.75 | 2.25 | 2.00 | 2.00 | 1.50 | 0.75 | 0.75 | 1.00 | 1.50 | 0.67 | 0.67 | 1.00 | 1.25 | 1.00 | 0.75 | 1.00 | 1.00 | 1.50 | 53.16 |
| i | 0.75 | 0.75 | 1.00 | 0.00 | 0.00 | 0.00 | 0.75 | 1.25 | 1.25 | 1.00 | 1.75 | 1.50 | 1.00 | 0.50 | 0.75 | 0.25 | 0.33 | 0.00 | 0.00 | 0.00 | 0.00 | 0.25 | 0.33 | 0.33 | 0.75 | 0.00 | 0.00 | 0.25 | 0.00 | 0.00 | 0.49 | 17.46 |
| c | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.25 | 0.50 | 0.50 | 0.00 | 0.00 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.33 | 0.25 | 0.25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.09 | 3.06 |
| CV | 39.50 | 39.50 | 33.67 | 45.33 | 46.00 | 47.00 | 83.00 | 105.25 | 111.00 | 120.00 | 123.75 | 107.00 | 118.75 | 107.75 | 79.00 | 85.75 | 49.67 | 49.75 | 13.50 | 10.00 | 17.00 | 24.25 | 33.67 | 35.00 | 35.00 | 28.25 | 21.67 | 32.25 | 18.00 | 24.50 | 56.16 | 100 |
| CVn | 39.50 | 39.50 | 28.33 | 22.33 | 11.00 | 19.25 | 26.75 | 21.75 | 19.25 | 26.75 | 37.00 | 24.50 | 36.00 | 46.25 | 42.00 | 53.50 | 32.33 | 22.25 | 13.50 | 10.00 | 9.67 | 6.00 | 0.33 | 0.00 | 0.00 | 0.00 | 0.33 | 0.25 | 0.25 | 0.00 | 19.62 | 34.94 |
| CVs | 0.00 | 0.00 | 5.33 | 23.00 | 35.00 | 27.75 | 56.25 | 83.50 | 91.75 | 93.25 | 86.75 | 82.50 | 82.75 | 61.50 | 37.00 | 32.25 | 17.33 | 27.50 | 0.00 | 0.00 | 7.33 | 18.25 | 33.33 | 35.00 | 35.00 | 28.25 | 21.33 | 32.00 | 17.75 | 24.50 | 36.54 | 65.06 |
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