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% 2012.1670 MAR 73.0 68.7 65.5 10.2 9.0 8.4 2012.2503 APR 81.2 70.7 64.1 11.0 9.0 7.8 2012.3337 MAY 88.9 72.5 61.0 11.0 8.7 7.3 2012.4170 JUN 94.4 73.9 59.0 11.2 8.8 7.1 2012.5003 JUL 101.2 75.1 56.6 11.6 9.2 7.6 2012.5837 AUG 106.2 76.0 53.7 12.1 9.7 8.3 2012.6670 SEP 110.2 77.0 51.1 12.3 10.0 8.5 2012.7503 OCT 113.8 78.1 49.2 12.8 10.2 8.5 2012.8337 NOV 117.3 79.1 48.0 13.1 10.3 8.4 2012.9170 DEC 122.6 80.0 48.2 13.3 10.3 8.4 2013.0003 JAN 124.0 79.7 47.8 13.3 10.3 7.8 2013.0837 FEB 121.2 79.2 45.9 13.9 10.6 7.7 2013.1670 MAR 118.4 79.4 45.0 13.8 10.5 7.4 2013.2503 APR 118.8 80.0 45.8 13.1 10.1 6.8 2013.3337 MAY 120.5 80.5 47.4 12.6 9.9 7.0 2013.4170 JUN 121.1 80.4 47.0 13.5 9.8 7.2 2013.5003 JUL 121.2 80.3 47.9 14.4 9.8 6.4 2013.5837 AUG 120.4 80.1 48.1 15.1 10.0 6.3 2013.6670 SEP 118.2 79.9 45.0 16.0 10.1 6.1 2013.7503 OCT 114.6 79.6 41.8 16.2 10.0 5.8 2013.8337 NOV 109.6 79.0 40.0 15.7 10.2 6.1 2013.9170 DEC 107.1 78.4 38.2 16.0 10.4 6.5 2014.0003 JAN 104.3 77.8 37.4 16.1 11.0 7.3 2014.0837 FEB 100.7 76.6 35.9 16.1 11.4 7.9 2014.1670 MAR 98.6 75.0 34.0 16.1 11.5 8.2 2014.2503 APR 99.1 73.5 32.7 15.9 11.7 8.3 2014.3337 MAY 99.3 72.7 32.0 16.1 12.0 8.4 2014.4170 JUN 99.5 72.0 31.8 17.1 12.7 8.6 2014.5003 JUL 99.7 70.8 31.9 18.1 13.3 9.0 2014.5837 AUG 102.0 69.5 31.9 18.9 13.3 9.1 2014.6670 SEP 105.2 68.7 31.2 19.7 13.4 8.9 2014.7503 OCT 106.7 68.3 30.4 19.9 13.5 8.8 2014.8337 NOV 105.7 67.7 30.0 20.0 13.5 8.6 2014.9170 DEC 104.9 66.3 27.5 20.6 13.7 8.5 2015.0003 JAN 104.9 64.9 24.7 21.3 14.1 8.5 2015.0837 FEB 103.4 63.7 23.9 21.5 14.5 8.4 2015.1670 MAR 101.5 62.9 24.2 21.6 15.1 9.0 2015.2503 APR 98.7 62.1 24.7 22.2 15.8 9.7 2015.3337 MAY 95.4 61.3 24.8 22.7 16.6 10.8 2015.4170 JUN 93.2 60.3 24.2 22.9 17.1 11.5 2015.5003 JUL 92.1 59.1 23.1 22.2 17.2 11.6 2015.5837 AUG 89.7 57.7 21.9 21.4 17.3 11.9 2015.6670 SEP 85.4 56.0 21.1 21.3 17.4 12.3 2015.7503 OCT 80.8 54.2 20.8 22.0 17.5 12.8 2015.8337 NOV 79.1 52.6 20.0 22.8 17.8 13.9 2015.9170 DEC 77.2 50.9 18.9 23.8 18.1 14.9 2016.0003 JAN 76.4 49.4 18.0 24.2 18.2 14.7 2016.0837 FEB 75.7 48.4 17.8 23.7 17.8 14.5 2016.1670 MAR 75.0 47.3 16.8 23.3 17.2 14.1 2016.2503 APR 74.4 46.1 14.5 23.1 16.6 13.2 2016.3337 MAY 74.7 45.0 12.7 23.1 16.0 12.4 2016.4170 JUN 74.3 43.9 12.1 23.6 15.7 11.5 2016.5003 JUL 72.1 42.4 11.1 23.9 15.2 10.2 2016.5837 AUG 71.4 40.9 9.9 24.0 14.7 9.5 2016.6670 SEP 70.5 39.8 8.8 24.2 14.5 9.0 2016.7503 OCT 67.9 38.5 8.2 24.3 14.4 8.9 2016.8337 NOV 65.7 37.3 7.7 24.3 14.4 9.1 2016.9170 DEC 64.3 35.9 6.5 24.1 14.5 9.7 2017.0003 JAN 63.7 34.6 5.6 23.6 14.7 10.5 2017.0837 FEB 62.8 33.7 5.4 23.1 15.0 11.4 2017.1670 MAR 60.4 32.8 5.5 23.2 15.5 12.0 2017.2503 APR 57.1 31.6 5.9 23.2 15.8 12.0 2017.3337 MAY 54.1 30.2 6.4 23.1 16.2 12.1 2017.4170 JUN 51.3 29.1 6.6 22.7 16.2 12.6 2017.5003 JUL 50.0 28.4 6.5 22.1 16.2 12.8 2017.5837 AUG 49.0 27.5 6.8 21.4 16.0 12.3 2017.6670 SEP 47.7 26.3 7.2 20.8 15.9 12.2 2017.7503 OCT 45.4 25.1 6.5 20.9 15.7 11.9 2017.8337 NOV 43.5 24.2 6.2 20.7 15.5 11.3 2017.9170 DEC 42.7 23.3 6.1 20.3 15.4 10.9 2018.0003 JAN 40.9 22.2 5.9 19.9 15.5 10.5 2018.0837 FEB 38.6 21.2 5.5 19.2 15.5 10.0 2018.1670 MAR 37.6 20.1 4.9 19.2 15.5 9.4 2018.2503 APR 36.7 19.1 4.3 18.8 15.2 8.9 2018.3337 MAY 34.9 18.1 3.9 18.8 15.1 9.1 2018.4170 JUN 33.1 17.1 3.6 18.7 15.3 9.4 2018.5003 JUL 31.3 16.2 3.3 18.5 15.5 10.1 2018.5837 AUG 29.5 15.2 3.0 18.9 15.6 10.6 2018.6670 SEP 27.7 14.3 2.7 19.4 15.7 10.8 2018.7503 OCT 26.0 13.4 2.4 18.5 15.0 10.4 2018.8337 NOV 24.4 12.5 2.1 17.7 14.3 10.1 2018.9170 DEC 22.8 11.7 1.9 16.9 13.7 9.7 2019.0003 JAN 21.3 10.9 1.6 16.1 13.1 9.3 2019.0837 FEB 19.9 10.1 1.3 15.4 12.4 9.0 2019.1670 MAR 18.6 9.4 1.1 14.6 11.9 8.6 2019.2503 APR 17.4 8.8 0.9 14.0 11.3 8.3 2019.3337 MAY 16.2 8.2 0.7 13.3 10.8 8.0 2019.4170 JUN 15.2 7.6 0.5 12.8 10.4 7.8 2019.5003 JUL 14.4 7.2 0.4 12.3 10.0 7.5 2019.5837 AUG 13.6 6.8 0.3 11.9 9.6 7.3 2019.6670 SEP 13.1 6.5 0.2 11.5 9.3 7.2 2019.7503 OCT 12.6 6.3 0.1 11.3 9.1 7.0 2019.8337 NOV 12.4 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