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% 2009.1670 MAR 3.9 2.5 1.5 4.9 4.6 4.5 2009.2503 APR 5.7 3.0 1.6 5.1 4.8 4.4 2009.3337 MAY 7.3 3.6 1.2 5.5 5.0 4.7 2009.4170 JUN 9.6 4.1 1.3 6.0 5.3 4.6 2009.5003 JUL 11.7 4.8 1.0 6.3 5.3 4.4 2009.5837 AUG 13.5 5.7 0.5 6.7 5.3 4.2 2009.6670 SEP 16.2 6.6 0.4 7.1 5.2 3.9 2009.7503 OCT 19.6 7.5 0.7 7.1 5.2 3.7 2009.8337 NOV 24.7 8.6 0.8 7.0 5.2 3.5 2009.9170 DEC 28.8 9.8 0.0 6.9 4.9 3.3 2010.0003 JAN 31.6 11.0 0.0 6.5 4.3 2.7 2010.0837 FEB 35.9 12.3 0.0 6.2 3.8 2.0 2010.1670 MAR 41.1 13.9 0.0 6.0 3.5 1.4 2010.2503 APR 47.1 15.8 0.0 5.9 3.1 0.6 2010.3337 MAY 54.0 17.7 0.0 6.7 3.2 0.3 2010.4170 JUN 61.4 19.8 0.0 7.5 3.4 0.2 2010.5003 JUL 66.8 22.2 0.0 7.4 3.4 0.0 2010.5837 AUG 70.5 24.7 0.0 7.1 3.2 -0.2 2010.6670 SEP 74.1 27.3 0.0 6.1 2.8 -0.6 2010.7503 OCT 80.3 29.9 0.0 5.3 2.5 -0.6 2010.8337 NOV 87.9 32.2 0.0 4.7 2.5 -0.4 2010.9170 DEC 96.4 34.5 0.6 4.3 2.6 -0.3 2011.0003 JAN 104.0 37.0 1.4 5.2 2.9 0.2 2011.0837 FEB 110.5 39.3 2.5 6.8 3.8 1.7 2011.1670 MAR 117.5 41.6 2.7 7.7 4.8 2.8 2011.2503 APR 124.2 44.1 3.8 7.6 5.1 2.8 2011.3337 MAY 127.9 46.0 4.6 8.0 5.4 2.9 2011.4170 JUN 128.7 47.6 5.3 8.6 5.7 2.4 2011.5003 JUL 130.8 49.4 6.0 9.2 5.7 1.9 2011.5837 AUG 133.9 51.0 6.6 9.6 6.2 2.2 2011.6670 SEP 137.5 52.8 7.6 10.3 6.8 2.5 2011.7503 OCT 143.2 54.7 7.3 11.4 7.4 2.9 2011.8337 NOV 146.6 56.4 5.8 12.3 7.9 3.0 2011.9170 DEC 147.5 57.9 5.2 12.7 8.1 2.7 2012.0003 JAN 151.2 59.8 5.5 12.9 8.6 2.6 2012.0837 FEB 156.3 61.6 6.8 12.6 9.0 2.6 2012.1670 MAR 159.3 63.0 7.9 12.7 9.1 2.6 2012.2503 APR 161.6 64.2 7.9 12.9 8.9 2.4 2012.3337 MAY 164.4 65.2 7.6 13.4 8.6 1.9 2012.4170 JUN 166.8 66.4 7.7 14.1 9.0 2.3 2012.5003 JUL 168.6 67.7 7.8 14.7 10.0 3.6 2012.5837 AUG 170.7 69.0 9.6 15.2 10.7 4.9 2012.6670 SEP 172.0 70.3 11.0 15.1 10.9 5.5 2012.7503 OCT 171.1 70.5 11.5 14.5 10.6 5.6 2012.8337 NOV 170.2 70.8 12.7 14.4 10.6 5.7 2012.9170 DEC 171.4 71.7 14.4 14.0 10.4 5.6 2013.0003 JAN 172.1 71.8 16.2 12.9 10.0 5.2 2013.0837 FEB 170.1 71.9 18.3 12.4 9.9 5.4 2013.1670 MAR 166.9 72.8 21.4 11.8 9.0 5.0 2013.2503 APR 163.6 73.9 24.6 11.3 8.1 4.4 2013.3337 MAY 161.6 74.3 27.0 11.8 7.9 4.1 2013.4170 JUN 160.9 74.1 28.4 12.5 7.5 3.4 2013.5003 JUL 160.0 74.2 29.9 13.1 7.2 2.9 2013.5837 AUG 159.4 74.5 31.7 13.3 7.0 3.0 2013.6670 SEP 158.6 74.6 33.5 13.9 6.9 2.9 2013.7503 OCT 158.9 74.6 34.2 14.0 6.7 2.6 2013.8337 NOV 159.7 74.3 33.7 13.7 7.1 3.1 2013.9170 DEC 159.5 74.3 34.0 14.1 7.5 3.7 2014.0003 JAN 158.3 74.3 35.6 13.7 7.7 4.6 2014.0837 FEB 155.2 73.3 36.5 12.0 7.9 4.7 2014.1670 MAR 150.4 70.8 33.8 11.7 7.9 4.6 2014.2503 APR 146.7 68.7 31.3 12.2 8.3 4.8 2014.3337 MAY 143.1 67.1 29.2 12.6 8.7 5.2 2014.4170 JUN 138.4 65.4 27.3 13.6 9.3 6.1 2014.5003 JUL 134.8 63.6 26.2 14.2 9.6 6.5 2014.5837 AUG 131.3 61.8 25.2 13.2 9.1 6.1 2014.6670 SEP 127.8 60.9 24.1 12.4 8.7 5.7 2014.7503 OCT 125.3 60.8 24.3 12.2 8.9 5.6 2014.8337 NOV 121.7 60.4 24.7 12.1 8.7 5.3 2014.9170 DEC 118.1 59.0 23.4 12.6 8.6 4.9 2015.0003 JAN 114.7 57.8 22.8 12.9 8.5 4.6 2015.0837 FEB 112.0 57.2 23.0 13.9 8.9 4.5 2015.1670 MAR 110.4 56.5 21.7 15.6 10.0 5.3 2015.2503 APR 108.5 55.7 20.4 16.7 10.7 6.1 2015.3337 MAY 106.1 54.8 19.9 17.6 11.4 7.1 2015.4170 JUN 102.3 53.6 19.0 18.1 11.9 7.2 2015.5003 JUL 97.0 52.4 17.9 17.9 12.3 7.7 2015.5837 AUG 92.7 51.6 17.1 17.8 12.8 8.6 2015.6670 SEP 88.7 50.4 16.8 17.3 13.2 9.3 2015.7503 OCT 83.7 48.5 16.6 18.2 13.5 10.0 2015.8337 NOV 78.9 46.2 16.1 19.0 14.1 10.5 2015.9170 DEC 75.2 43.6 14.8 19.5 14.8 10.9 2016.0003 JAN 71.6 41.3 13.6 20.4 15.2 11.0 2016.0837 FEB 67.0 39.7 13.5 20.2 15.1 10.5 2016.1670 MAR 64.3 38.3 12.9 20.2 14.8 10.1 2016.2503 APR 65.0 37.2 10.6 20.4 14.4 9.8 2016.3337 MAY 65.9 36.3 8.5 20.5 13.9 9.2 2016.4170 JUN 66.5 35.6 7.9 21.0 13.6 8.3 2016.5003 JUL 65.6 34.5 7.0 21.2 13.1 7.0 2016.5837 AUG 65.5 33.6 6.5 21.1 12.2 6.1 2016.6670 SEP 64.7 32.6 5.6 21.1 11.9 5.7 2016.7503 OCT 62.0 31.2 4.8 21.2 11.8 5.4 2016.8337 NOV 59.9 30.2 4.3 20.8 11.5 5.1 2016.9170 DEC 58.7 29.5 3.6 19.8 11.0 4.8 2017.0003 JAN 58.5 29.0 3.1 18.9 10.8 5.0 2017.0837 FEB 58.2 28.6 2.9 18.4 11.1 5.6 2017.1670 MAR 56.3 27.9 3.1 18.6 11.8 6.5 2017.2503 APR 53.4 27.2 3.7 18.5 12.1 6.7 2017.3337 MAY 49.9 26.1 4.2 18.6 12.7 7.4 2017.4170 JUN 47.4 25.0 4.0 18.8 13.2 8.3 2017.5003 JUL 47.0 24.4 4.1 18.8 13.6 9.1 2017.5837 AUG 46.3 23.8 4.3 19.0 13.7 9.6 2017.6670 SEP 43.6 22.3 4.5 19.4 13.8 10.3 2017.7503 OCT 41.1 20.9 3.9 19.7 13.9 10.2 2017.8337 NOV 39.9 20.1 3.7 19.7 14.1 9.9 2017.9170 DEC 39.1 19.3 3.7 19.7 14.5 9.9 2018.0003 JAN 37.3 18.3 3.5 19.8 15.3 10.1 2018.0837 FEB 34.5 17.2 3.0 19.6 15.9 10.1 2018.1670 MAR 33.0 16.5 2.8 19.8 16.2 9.7 2018.2503 APR 31.5 15.7 2.6 19.6 16.0 9.3 2018.3337 MAY 30.0 15.0 2.4 19.3 15.7 9.2 2018.4170 JUN 28.5 14.2 2.2 18.6 15.4 9.3 2018.5003 JUL 27.1 13.5 2.0 18.8 15.7 10.0 2018.5837 AUG 25.6 12.8 1.8 19.5 16.2 10.7 2018.6670 SEP 24.3 12.1 1.6 20.0 16.5 11.0 2018.7503 OCT 22.9 11.4 1.5 20.1 16.5 11.3 2018.8337 NOV 21.6 10.8 1.3 19.8 16.2 11.1 2018.9170 DEC 20.4 10.1 1.1 18.8 15.4 10.7 2019.0003 JAN 19.2 9.6 1.0 17.8 14.6 10.2 2019.0837 FEB 18.1 9.0 0.8 16.8 13.8 9.7 2019.1670 MAR 17.1 8.5 0.7 15.9 13.0 9.3 2019.2503 APR 16.2 8.0 0.5 15.0 12.2 8.8 2019.3337 MAY 15.3 7.6 0.4 14.2 11.6 8.4 2019.4170 JUN 14.5 7.2 0.3 13.4 10.9 8.1 2019.5003 JUL 13.9 6.9 0.2 12.7 10.4 7.8 2019.5837 AUG 13.3 6.6 0.2 12.2 9.9 7.5 2019.6670 SEP 12.9 6.4 0.1 11.7 9.5 7.3 2019.7503 OCT 12.5 6.2 0.1 11.3 9.2 7.1 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