TABLE 4 ESTIMATES OF 13-MONTH SMOOTH SOLAR ACTIVITY FOR BALANCE OF CYCLE 24 CYCLE 25 AND BEGINNING OF CYCLE 26 TIME SUNSPOT NUMBERS GEOMAGNETIC INDEX (Ap) PERCENTILE PERCENTILE 95.0% 50% 5.0% 95.0% 50% 5.0% 2009.5837 AUG 6.1 4.1 2.6 3.9 3.5 3.4 2009.6670 SEP 9.1 4.6 2.3 4.0 3.3 2.9 2009.7503 OCT 11.1 5.0 1.8 4.2 3.2 2.7 2009.8337 NOV 12.6 5.4 0.7 4.7 3.2 2.5 2009.9170 DEC 14.5 6.1 0.0 4.7 2.9 1.9 2010.0003 JAN 16.6 6.9 0.0 4.1 2.2 0.9 2010.0837 FEB 19.7 7.7 0.0 4.5 2.0 0.3 2010.1670 MAR 23.6 8.7 0.0 4.9 1.8 0.0 2010.2503 APR 28.0 10.2 0.0 5.2 1.5 0.0 2010.3337 MAY 33.7 11.4 0.0 6.4 1.9 0.0 2010.4170 JUN 40.2 12.7 0.0 7.6 2.4 0.0 2010.5003 JUL 47.0 14.8 0.0 7.9 2.6 0.0 2010.5837 AUG 53.4 17.4 0.0 7.6 2.6 0.0 2010.6670 SEP 59.4 20.0 0.0 6.5 1.9 0.0 2010.7503 OCT 65.4 22.7 0.0 5.2 1.2 0.0 2010.8337 NOV 72.7 25.0 1.3 4.3 0.8 0.0 2010.9170 DEC 80.5 27.0 1.4 3.7 0.8 0.0 2011.0003 JAN 87.4 29.4 1.4 3.7 1.0 0.0 2011.0837 FEB 93.9 31.6 1.1 4.5 1.8 0.0 2011.1670 MAR 101.0 33.7 0.6 5.3 2.6 0.1 2011.2503 APR 108.6 36.4 1.2 5.2 2.9 0.1 2011.3337 MAY 112.8 38.5 2.0 5.6 3.3 0.2 2011.4170 JUN 114.7 40.7 3.4 6.4 3.7 0.0 2011.5003 JUL 118.1 42.9 3.9 7.2 4.0 0.0 2011.5837 AUG 121.6 44.4 3.1 7.5 4.4 0.0 2011.6670 SEP 125.4 46.1 3.4 8.3 5.1 0.4 2011.7503 OCT 131.1 48.0 5.1 9.7 6.0 1.2 2011.8337 NOV 135.6 50.4 6.8 10.9 6.7 1.5 2011.9170 DEC 138.5 53.2 8.1 11.7 7.2 1.7 2012.0003 JAN 143.4 56.2 10.8 12.5 8.0 1.9 2012.0837 FEB 149.1 58.7 14.8 13.6 8.6 2.2 2012.1670 MAR 152.7 61.1 18.8 14.5 9.1 2.9 2012.2503 APR 155.8 63.5 21.2 15.3 9.4 3.3 2012.3337 MAY 159.2 65.6 21.3 16.1 9.4 3.2 2012.4170 JUN 162.0 67.4 20.9 16.7 9.9 3.6 2012.5003 JUL 164.5 69.4 21.3 16.9 10.8 4.9 2012.5837 AUG 166.9 71.6 23.3 17.4 11.6 6.3 2012.6670 SEP 169.2 73.7 24.9 17.3 11.9 7.1 2012.7503 OCT 169.0 74.6 26.2 16.9 11.8 7.4 2012.8337 NOV 168.5 75.5 27.5 17.2 12.0 7.9 2012.9170 DEC 170.4 76.6 27.9 16.8 11.9 7.8 2013.0003 JAN 171.7 76.7 28.4 15.3 11.0 6.7 2013.0837 FEB 169.9 76.8 28.7 13.8 10.4 6.3 2013.1670 MAR 167.2 78.0 29.8 11.9 8.9 5.1 2013.2503 APR 164.5 79.6 32.2 10.4 7.4 3.6 2013.3337 MAY 163.0 80.2 33.9 10.2 6.9 2.9 2013.4170 JUN 162.4 80.1 34.3 10.6 6.4 2.1 2013.5003 JUL 161.8 80.2 34.1 11.0 5.9 1.5 2013.5837 AUG 161.4 80.7 35.2 11.2 5.8 1.5 2013.6670 SEP 160.8 80.9 36.5 11.6 5.5 1.3 2013.7503 OCT 160.3 80.6 36.0 11.8 5.4 1.0 2013.8337 NOV 159.3 79.8 33.8 11.9 6.1 1.9 2013.9170 DEC 159.0 79.4 32.9 12.3 6.5 2.4 2014.0003 JAN 157.9 79.2 33.3 11.7 6.6 2.8 2014.0837 FEB 154.9 78.1 32.7 11.5 6.9 3.4 2014.1670 MAR 150.3 76.0 30.6 12.2 7.5 4.1 2014.2503 APR 147.3 74.1 28.4 13.6 8.2 5.0 2014.3337 MAY 143.9 72.7 26.4 14.0 8.6 5.6 2014.4170 JUN 139.2 71.2 24.6 14.4 9.3 5.9 2014.5003 JUL 135.5 69.5 23.6 14.5 9.7 6.3 2014.5837 AUG 132.0 67.9 23.4 13.3 8.8 5.6 2014.6670 SEP 129.1 67.3 24.5 13.0 8.2 5.0 2014.7503 OCT 126.9 67.4 26.3 13.6 8.3 4.8 2014.8337 NOV 123.7 67.0 27.2 13.0 7.8 4.2 2014.9170 DEC 121.3 65.8 26.3 12.0 7.3 3.6 2015.0003 JAN 121.4 64.9 26.5 11.5 7.0 2.9 2015.0837 FEB 119.6 64.3 26.7 11.3 7.3 2.8 2015.1670 MAR 116.8 63.4 25.3 12.3 8.2 3.8 2015.2503 APR 112.8 62.2 23.7 13.3 8.7 4.4 2015.3337 MAY 108.6 61.0 22.9 14.4 9.4 4.5 2015.4170 JUN 105.2 59.7 22.0 15.1 10.1 4.6 2015.5003 JUL 103.5 58.6 21.0 15.2 10.7 5.3 2015.5837 AUG 100.8 57.6 20.3 15.3 11.4 6.5 2015.6670 SEP 95.3 56.1 19.8 15.8 11.9 7.5 2015.7503 OCT 89.0 54.2 19.7 17.0 12.3 8.9 2015.8337 NOV 84.9 52.0 19.3 17.9 13.0 9.9 2015.9170 DEC 83.0 49.7 18.0 18.9 14.0 10.0 2016.0003 JAN 81.3 47.7 17.0 20.0 14.6 10.4 2016.0837 FEB 78.9 46.3 17.1 19.9 14.6 10.4 2016.1670 MAR 76.4 45.0 16.0 20.2 14.6 10.4 2016.2503 APR 74.0 43.9 13.6 20.6 14.4 10.3 2016.3337 MAY 71.8 43.1 12.1 20.7 13.9 9.7 2016.4170 JUN 69.7 42.5 11.4 20.9 13.3 8.5 2016.5003 JUL 67.1 41.0 10.5 20.9 12.5 7.0 2016.5837 AUG 66.9 39.7 9.7 20.8 11.7 6.3 2016.6670 SEP 66.1 38.7 8.8 20.9 11.3 5.9 2016.7503 OCT 64.5 37.2 7.8 20.9 11.1 5.5 2016.8337 NOV 64.1 36.2 7.5 20.3 10.6 5.1 2016.9170 DEC 64.1 35.5 7.1 19.4 10.1 4.9 2017.0003 JAN 63.0 34.8 7.0 18.4 9.9 5.0 2017.0837 FEB 61.5 34.3 6.7 17.8 10.1 5.5 2017.1670 MAR 59.2 33.7 6.5 17.9 10.9 6.1 2017.2503 APR 55.3 32.9 6.9 17.9 11.3 6.5 2017.3337 MAY 51.6 31.6 7.1 18.4 12.1 7.4 2017.4170 JUN 48.3 30.3 6.8 18.8 13.0 8.7 2017.5003 JUL 49.5 29.8 7.0 19.2 13.7 9.7 2017.5837 AUG 48.8 29.2 7.2 19.1 14.0 10.4 2017.6670 SEP 45.9 27.5 6.7 19.7 14.3 10.6 2017.7503 OCT 43.3 25.8 6.1 20.2 14.6 10.8 2017.8337 NOV 41.2 24.5 5.9 20.4 15.0 10.8 2017.9170 DEC 40.2 23.2 5.4 20.6 15.8 11.2 2018.0003 JAN 38.0 21.6 4.6 21.1 17.1 12.1 2018.0837 FEB 35.3 20.1 4.0 21.7 18.4 13.0 2018.1670 MAR 33.0 18.8 3.1 22.7 19.1 13.1 2018.2503 APR 31.5 17.9 2.9 22.9 19.2 13.0 2018.3337 MAY 30.0 17.0 2.7 22.5 18.9 12.9 2018.4170 JUN 28.6 16.1 2.4 21.7 18.4 12.7 2018.5003 JUL 27.2 15.2 2.2 21.8 18.6 13.3 2018.5837 AUG 25.7 14.4 2.0 22.2 19.2 14.3 2018.6670 SEP 24.4 13.5 1.8 22.6 19.5 14.7 2018.7503 OCT 23.0 12.7 1.6 22.7 19.4 14.9 2018.8337 NOV 21.7 11.9 1.4 22.2 19.0 14.7 2018.9170 DEC 20.5 11.1 1.2 20.9 17.9 13.8 2019.0003 JAN 19.3 10.4 1.1 19.7 16.7 12.9 2019.0837 FEB 18.2 9.7 0.9 18.4 15.6 12.0 2019.1670 MAR 17.2 9.1 0.7 17.2 14.5 11.2 2019.2503 APR 16.2 8.5 0.6 16.1 13.5 10.4 2019.3337 MAY 15.3 8.0 0.5 15.0 12.5 9.7 2019.4170 JUN 14.6 7.5 0.4 14.1 11.7 9.0 2019.5003 JUL 13.9 7.1 0.3 13.2 10.9 8.4 2019.5837 AUG 13.3 6.7 0.2 12.5 10.2 7.9 2019.6670 SEP 12.9 6.4 0.1 11.9 9.7 7.5 2019.7503 OCT 12.6 6.2 0.1 11.4 9.3 7.2 2019.8337 NOV 12.3 6.1 0.0 11.1 9.0 7.0 2019.9170 DEC 12.3 6.1 0.0 11.1 9.0 6.9 2020.0003 JAN 12.9 6.5 0.4 11.3 9.0 6.9 2020.0837 FEB 14.2 7.2 0.9 11.6 9.2 7.1 2020.1670 MAR 15.4 7.8 1.2 11.7 9.3 7.4 2020.2503 APR 16.6 8.5 1.7 11.9 9.4 7.5 2020.3337 MAY 18.1 9.3 1.8 12.0 9.5 7.5 2020.4170 JUN 20.6 10.2 2.3 12.1 9.6 7.3 2020.5003 JUL 23.0 11.2 2.9 12.2 9.7 7.2 2020.5837 AUG 25.1 12.3 3.1 12.5 9.9 7.1 2020.6670 SEP 28.3 13.6 3.2 12.8 10.1 7.0 2020.7503 OCT 32.2 15.1 3.5 13.2 10.5 7.2 2020.8337 NOV 38.2 16.9 3.5 13.7 10.8 7.6 2020.9170 DEC 43.7 19.0 3.5 14.5 11.1 7.9 2021.0003 JAN 47.9 21.0 4.2 15.7 11.4 7.7 2021.0837 FEB 54.1 23.4 4.3 16.1 11.6 7.7 2021.1670 MAR 60.7 25.9 4.3 16.3 11.8 7.6 2021.2503 APR 66.8 28.4 4.8 16.8 12.0 7.6 2021.3337 MAY 74.4 31.2 4.8 18.0 12.3 7.6 2021.4170 JUN 83.1 34.5 5.2 18.9 12.6 7.7 2021.5003 JUL 89.9 37.8 5.8 19.1 12.7 7.7 2021.5837 AUG 95.1 41.3 6.8 19.2 12.9 7.8 2021.6670 SEP 100.0 44.8 7.7 19.0 13.1 7.7 2021.7503 OCT 105.0 48.2 9.1 18.6 13.1 7.7 2021.8337 NOV 110.5 51.5 9.8 18.5 13.2 7.8 2021.9170 DEC 116.5 54.9 9.9 18.9 13.4 8.0 2022.0003 JAN 122.0 58.5 11.2 18.8 13.5 8.2 2022.0837 FEB 126.8 62.1 12.4 17.8 13.5 8.6 2022.1670 MAR 134.1 65.8 13.4 17.9 13.7 8.7 2022.2503 APR 141.4 69.4 14.6 18.5 13.9 8.7 2022.3337 MAY 146.1 72.7 15.1 19.1 14.2 9.0 2022.4170 JUN 147.9 75.6 15.6 19.6 14.6 9.4 2022.5003 JUL 151.0 78.5 16.2 20.3 14.9 9.6 2022.5837 AUG 154.7 80.9 16.7 20.3 15.1 9.6 2022.6670 SEP 158.4 83.0 17.1 20.3 15.1 9.8 2022.7503 OCT 163.8 85.3 17.1 20.5 15.2 10.0 2022.8337 NOV 167.3 87.7 16.7 20.8 15.4 10.5 2022.9170 DEC 169.1 90.1 16.4 21.2 15.4 11.1 2023.0003 JAN 172.9 92.3 16.8 21.3 15.3 11.6 2023.0837 FEB 177.6 94.2 17.5 21.4 15.1 11.3 2023.1670 MAR 180.4 96.2 18.7 21.6 15.0 11.2 2023.2503 APR 182.4 98.4 20.6 22.0 15.0 10.7 2023.3337 MAY 185.0 100.2 21.8 22.8 14.9 10.2 2023.4170 JUN 187.4 101.3 23.1 22.5 14.7 9.9 2023.5003 JUL 189.5 102.2 25.4 21.3 14.5 10.1 2023.5837 AUG 190.7 102.4 28.1 20.6 14.3 10.1 2023.6670 SEP 192.2 102.8 30.7 20.1 14.2 10.3 2023.7503 OCT 192.5 103.6 32.1 19.6 14.1 10.6 2023.8337 NOV 192.1 104.1 33.4 19.5 14.0 10.6 2023.9170 DEC 193.4 104.4 35.7 19.3 14.0 10.5 2024.0003 JAN 193.9 103.6 37.4 19.1 14.2 10.5 2024.0837 FEB 190.8 102.1 39.6 18.9 14.6 10.5 2024.1670 MAR 186.3 101.2 41.2 18.9 14.7 10.3 2024.2503 APR 181.9 100.7 42.7 19.5 14.6 9.8 2024.3337 MAY 179.6 100.4 43.9 20.4 14.7 10.2 2024.4170 JUN 178.9 100.1 43.8 22.0 15.0 10.7 2024.5003 JUL 177.8 99.7 43.3 23.4 15.3 10.7 2024.5837 AUG 176.5 99.1 44.0 24.0 15.4 10.9 2024.6670 SEP 175.3 98.5 45.9 25.1 15.7 11.1 2024.7503 OCT 174.5 98.0 46.0 25.6 15.9 11.3 2024.8337 NOV 173.4 97.4 45.1 24.9 15.9 11.5 2024.9170 DEC 172.3 96.6 44.4 24.8 15.9 11.7 2025.0003 JAN 170.7 95.7 44.9 23.9 15.8 11.9 2025.0837 FEB 168.1 94.1 45.4 22.1 15.8 11.8 2025.1670 MAR 164.2 92.1 44.3 22.4 15.9 12.0 2025.2503 APR 161.0 90.3 43.7 23.1 16.0 11.8 2025.3337 MAY 157.9 89.1 44.7 23.1 16.0 11.1 2025.4170 JUN 153.9 87.8 45.7 22.6 16.0 10.8 2025.5003 JUL 150.5 86.2 44.6 22.0 15.8 10.8 2025.5837 AUG 146.4 84.3 42.6 21.9 15.8 10.8 2025.6670 SEP 142.9 82.9 41.6 22.7 16.1 10.8 2025.7503 OCT 142.0 81.8 41.3 23.7 16.5 10.8 2025.8337 NOV 138.7 80.3 39.3 23.9 16.7 10.8 2025.9170 DEC 136.4 78.4 35.0 23.9 17.0 10.7 2026.0003 JAN 135.3 76.6 34.1 23.9 17.1 10.6 2026.0837 FEB 132.3 74.9 35.4 23.5 17.2 10.3 2026.1670 MAR 128.8 73.5 34.6 22.5 17.2 10.5 2026.2503 APR 124.8 72.3 32.7 22.7 17.2 10.7 2026.3337 MAY 120.7 71.1 31.7 23.0 17.4 11.4 2026.4170 JUN 117.2 69.7 30.9 23.1 17.6 11.9 2026.5003 JUL 114.8 68.0 29.4 22.5 17.8 12.0 2026.5837 AUG 110.8 66.0 27.7 21.7 17.6 12.1 2026.6670 SEP 104.4 63.7 26.7 21.2 17.4 12.3 2026.7503 OCT 97.6 61.3 26.3 21.7 17.0 12.5 2026.8337 NOV 93.7 59.4 26.6 21.7 16.9 13.3 2026.9170 DEC 92.5 57.7 25.8 22.1 16.9 13.1 2027.0003 JAN 91.4 56.1 24.3 22.6 17.0 12.8 2027.0837 FEB 88.9 54.7 24.4 22.3 16.8 13.1 2027.1670 MAR 86.8 53.1 23.8 22.4 16.5 12.7 2027.2503 APR 83.1 51.4 22.7 22.7 16.2 12.5 2027.3337 MAY 79.8 49.8 21.9 22.9 15.8 12.1 2027.4170 JUN 76.3 48.2 20.4 23.5 15.6 11.2 2027.5003 JUL 71.0 46.4 18.9 24.1 15.4 10.5 2027.5837 AUG 69.8 44.7 16.7 24.8 15.3 10.7 2027.6670 SEP 70.1 43.5 14.9 25.3 15.3 10.8 2027.7503 OCT 69.7 42.3 13.7 25.6 15.3 10.6 2027.8337 NOV 69.6 41.1 11.9 25.4 15.3 10.8 2027.9170 DEC 68.8 39.7 10.4 24.9 15.2 11.0 2028.0003 JAN 66.8 38.2 9.5 24.0 15.0 11.1 2028.0837 FEB 64.1 36.8 8.7 23.0 14.9 11.3 2028.1670 MAR 60.9 35.5 7.9 22.5 15.0 11.2 2028.2503 APR 56.4 34.1 7.8 22.1 15.1 11.1 2028.3337 MAY 52.1 32.5 7.9 21.8 15.2 11.2 2028.4170 JUN 49.0 31.3 7.6 21.4 15.3 11.4 2028.5003 JUL 49.8 30.5 7.5 20.7 15.2 11.5 2028.5837 AUG 49.0 29.5 7.4 19.9 14.9 11.3 2028.6670 SEP 46.4 28.2 7.1 20.0 14.7 11.1 2028.7503 OCT 44.0 26.8 6.5 20.1 14.6 10.8 2028.8337 NOV 42.0 25.7 6.5 19.9 14.3 10.1 2028.9170 DEC 40.9 24.9 6.1 19.5 14.2 9.6 2029.0003 JAN 39.5 23.8 5.5 19.0 14.1 9.1 2029.0837 FEB 38.8 22.8 5.2 18.3 14.1 8.6 2029.1670 MAR 38.1 21.9 4.6 17.3 14.0 8.0 2029.2503 APR 37.7 21.0 3.8 17.4 13.8 7.5 2029.3337 MAY 36.9 20.0 3.6 17.5 13.7 7.6 2029.4170 JUN 35.9 19.2 3.5 17.6 13.7 7.8 2029.5003 JUL 34.7 18.3 3.3 17.5 13.6 8.3 2029.5837 AUG 33.3 17.4 3.2 17.7 13.5 8.6 2029.6670 SEP 31.6 16.5 2.6 18.1 13.4 8.5 2029.7503 OCT 29.7 15.5 2.0 17.9 13.2 8.6 2029.8337 NOV 27.1 14.8 1.6 17.6 12.9 8.5 2029.9170 DEC 24.5 13.8 1.6 17.3 12.6 8.5 2030.0003 JAN 22.1 12.6 1.3 16.3 12.2 8.4 2030.0837 FEB 20.3 11.5 0.9 14.8 11.8 8.4 2030.1670 MAR 19.2 10.5 0.6 13.8 11.4 8.3 2030.2503 APR 18.9 9.7 0.6 13.9 11.0 8.2 2030.3337 MAY 18.5 9.1 0.5 13.6 10.6 8.2 2030.4170 JUN 18.2 8.5 0.4 13.2 10.3 7.9 2030.5003 JUL 16.8 8.0 0.3 12.9 9.9 7.4 2030.5837 AUG 15.9 7.5 0.2 12.6 9.7 7.1 2030.6670 SEP 15.8 7.0 0.1 11.9 9.5 7.3 2030.7503 OCT 15.0 6.5 0.0 11.4 9.4 7.1