K-indices are calculated for every 3-hour interval measuring the amplitudes of the H- and D-component magnetic fields from the quiet-day variations. The definition of the K-indices at Syowa Station is as follows:
| K | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| variation(nT) | 0-25 | 25-50 | 50-100 | 100-200 | 200-350 | 350-600 | 600-1000 | 1000-1650 | 1650-2500 | 2500- |
2.1. List of each year
00
01
02
03
04
05
06
07
08
09
1960
1970
1980
1990
2000
2010
2.2. Long-term Variation Plot with Sunspot Number
2.3. Averaged Seasonal Variation Plot
3.1. Whole list (from 1966)
3.2. Yearly mean value
3.3. Long term variation plot
3.4. Base Line Value