TABLE 5 ESTIMATES OF 13-MONTH SMOOTH SOLAR ACTIVITY FOR BALANCE OF CYCLE 24 CYCLE 25 AND BEGINNING OF CYCLE 26 TIME 10.7 CM SOLAR FLUX (F10.7) GEOMAGNETIC INDEX (Ap) PERCENTILE PERCENTILE 75.0% 50% 5.0% 75.0% 50% 5.0% 2011.5837 AUG 118.4 117.4 115.8 8.3 7.7 7.1 2011.6670 SEP 120.5 119.2 115.5 9.2 7.9 7.0 2011.7503 OCT 123.0 121.3 113.3 9.7 8.2 6.9 2011.8337 NOV 125.3 123.4 109.8 9.7 8.4 6.5 2011.9170 DEC 130.6 125.5 104.9 10.0 8.5 6.1 2012.0003 JAN 133.6 127.3 100.4 10.2 8.7 5.4 2012.0837 FEB 137.2 129.0 98.1 11.0 8.9 4.9 2012.1670 MAR 140.0 130.7 97.2 12.0 9.2 5.1 2012.2503 APR 140.5 132.5 98.5 12.8 9.3 5.3 2012.3337 MAY 142.1 134.0 99.1 13.1 9.2 4.9 2012.4170 JUN 143.2 135.1 97.9 13.7 9.5 5.0 2012.5003 JUL 146.5 136.2 96.0 14.0 10.1 5.6 2012.5837 AUG 149.7 136.9 93.8 14.4 10.7 6.3 2012.6670 SEP 151.9 137.2 93.2 14.5 10.9 6.9 2012.7503 OCT 152.7 137.8 95.7 14.3 10.9 7.3 2012.8337 NOV 156.1 138.4 97.2 14.5 11.1 7.6 2012.9170 DEC 156.4 138.8 98.7 14.6 11.0 7.7 2013.0003 JAN 153.1 138.3 98.5 14.2 10.8 7.6 2013.0837 FEB 151.3 137.2 97.5 14.3 10.8 8.0 2013.1670 MAR 153.8 136.7 97.0 14.0 10.4 7.3 2013.2503 APR 154.6 136.8 95.6 13.2 9.6 6.5 2013.3337 MAY 154.6 137.2 94.4 12.6 9.4 6.0 2013.4170 JUN 154.8 137.7 92.9 12.7 9.1 5.7 2013.5003 JUL 157.4 137.9 90.5 13.3 8.9 5.8 2013.5837 AUG 156.6 137.8 86.8 13.9 9.1 6.0 2013.6670 SEP 154.4 137.3 83.8 14.7 9.1 5.8 2013.7503 OCT 155.1 136.9 80.5 14.9 9.1 5.5 2013.8337 NOV 155.7 136.7 78.9 14.6 9.4 6.0 2013.9170 DEC 157.8 136.7 77.6 14.9 9.6 6.4 2014.0003 JAN 156.3 135.9 75.9 14.9 10.0 6.7 2014.0837 FEB 153.0 134.8 75.0 15.1 10.4 6.9 2014.1670 MAR 150.3 133.4 73.5 15.1 10.6 6.9 2014.2503 APR 151.0 131.8 72.4 15.5 11.0 7.2 2014.3337 MAY 148.6 130.3 71.3 15.8 11.4 7.8 2014.4170 JUN 142.3 129.3 71.3 16.7 12.2 8.2 2014.5003 JUL 140.2 128.2 71.7 17.3 12.8 8.8 2014.5837 AUG 138.7 126.8 72.8 16.6 12.7 8.7 2014.6670 SEP 139.0 125.4 74.3 17.1 12.6 8.4 2014.7503 OCT 138.4 124.4 75.6 17.5 12.8 8.4 2014.8337 NOV 137.4 123.5 76.6 17.1 12.7 8.2 2014.9170 DEC 136.5 122.6 78.0 17.5 12.8 7.9 2015.0003 JAN 134.6 121.2 79.3 18.2 13.0 7.9 2015.0837 FEB 133.3 119.6 79.7 18.6 13.4 7.8 2015.1670 MAR 132.4 118.6 80.4 19.3 14.2 8.4 2015.2503 APR 132.9 117.9 81.4 20.2 14.9 9.1 2015.3337 MAY 131.6 117.0 81.5 21.1 15.5 10.1 2015.4170 JUN 129.2 115.8 81.3 21.4 16.0 10.7 2015.5003 JUL 126.1 114.5 81.6 20.9 16.1 10.8 2015.5837 AUG 124.0 113.0 81.6 20.5 16.1 11.1 2015.6670 SEP 122.8 111.5 80.9 20.1 16.2 11.4 2015.7503 OCT 120.0 109.8 80.0 20.9 16.1 11.8 2015.8337 NOV 118.5 108.1 79.4 21.3 16.4 13.0 2015.9170 DEC 116.3 106.6 79.3 22.1 16.9 13.0 2016.0003 JAN 115.5 105.3 79.5 22.6 17.0 12.8 2016.0837 FEB 115.5 103.9 79.1 22.0 16.6 12.7 2016.1670 MAR 114.8 102.6 78.6 21.6 16.0 11.9 2016.2503 APR 113.4 101.5 77.4 21.6 15.4 11.2 2016.3337 MAY 111.3 100.2 75.4 21.7 15.0 10.6 2016.4170 JUN 110.1 98.9 74.3 22.1 14.6 9.6 2016.5003 JUL 108.7 97.7 73.8 22.2 14.0 8.2 2016.5837 AUG 107.4 96.6 72.8 22.2 13.4 7.5 2016.6670 SEP 106.1 95.6 72.1 22.3 13.1 7.1 2016.7503 OCT 104.4 94.6 71.7 22.4 13.1 6.8 2016.8337 NOV 103.7 93.7 71.6 22.2 12.9 6.8 2016.9170 DEC 101.8 92.7 71.2 21.7 12.8 7.1 2017.0003 JAN 99.9 91.5 70.6 21.0 12.8 7.5 2017.0837 FEB 99.1 90.5 70.3 20.6 13.2 8.3 2017.1670 MAR 98.9 89.7 70.4 20.7 13.7 9.1 2017.2503 APR 98.5 88.8 70.7 20.5 14.0 9.2 2017.3337 MAY 98.2 87.7 70.8 20.4 14.2 9.5 2017.4170 JUN 97.3 86.7 71.0 20.1 14.4 9.9 2017.5003 JUL 96.0 85.9 70.9 19.8 14.5 10.3 2017.5837 AUG 95.2 85.1 70.9 19.5 14.4 10.6 2017.6670 SEP 93.4 84.3 71.0 19.8 14.4 10.8 2017.7503 OCT 90.0 83.2 70.6 20.0 14.3 10.6 2017.8337 NOV 89.7 82.2 70.0 19.8 14.3 10.1 2017.9170 DEC 88.2 81.4 69.8 19.6 14.5 9.8 2018.0003 JAN 86.8 80.8 69.8 19.4 14.8 9.7 2018.0837 FEB 85.9 80.1 69.6 19.0 15.2 9.5 2018.1670 MAR 84.9 79.4 69.4 19.0 15.4 9.0 2018.2503 APR 83.9 78.7 69.2 19.0 15.3 8.7 2018.3337 MAY 82.9 78.0 69.1 19.0 15.3 8.8 2018.4170 JUN 82.0 77.3 68.9 18.8 15.3 9.1 2018.5003 JUL 81.0 76.6 68.7 18.7 15.6 9.8 2018.5837 AUG 80.1 76.0 68.6 19.0 15.9 10.4 2018.6670 SEP 79.2 75.4 68.4 19.4 16.1 10.7 2018.7503 OCT 78.3 74.7 68.2 19.6 16.3 11.0 2018.8337 NOV 77.5 74.2 68.1 19.3 16.1 10.9 2018.9170 DEC 76.7 73.6 68.0 18.4 15.2 10.5 2019.0003 JAN 75.9 73.1 67.8 17.4 14.4 10.0 2019.0837 FEB 75.2 72.5 67.7 16.5 13.6 9.6 2019.1670 MAR 74.5 72.1 67.6 15.6 12.9 9.2 2019.2503 APR 73.9 71.6 67.5 14.8 12.2 8.8 2019.3337 MAY 73.4 71.2 67.4 14.0 11.5 8.4 2019.4170 JUN 72.9 70.9 67.3 13.3 10.9 8.0 2019.5003 JUL 72.4 70.6 67.2 12.7 10.3 7.7 2019.5837 AUG 72.1 70.3 67.1 12.1 9.9 7.5 2019.6670 SEP 71.8 70.1 67.1 11.7 9.5 7.2 2019.7503 OCT 71.6 70.0 67.0 11.3 9.2 7.1 2019.8337 NOV 71.4 69.9 67.0 11.1 9.0 7.0 2019.9170 DEC 71.4 69.9 67.0 11.1 9.0 6.9 2020.0003 JAN 71.9 70.0 67.0 11.3 9.0 6.9 2020.0837 FEB 72.1 70.3 67.1 11.6 9.2 7.1 2020.1670 MAR 72.8 70.7 67.2 11.7 9.3 7.4 2020.2503 APR 72.5 71.0 67.2 11.9 9.4 7.5 2020.3337 MAY 72.9 71.5 67.4 12.0 9.5 7.5 2020.4170 JUN 73.3 72.0 67.5 12.1 9.6 7.3 2020.5003 JUL 73.8 72.6 67.6 12.2 9.7 7.2 2020.5837 AUG 75.1 73.3 67.8 12.5 9.9 7.1 2020.6670 SEP 76.7 74.1 67.9 12.8 10.1 7.0 2020.7503 OCT 78.1 75.1 68.0 13.2 10.5 7.2 2020.8337 NOV 79.9 76.3 68.3 13.7 10.8 7.6 2020.9170 DEC 82.0 77.7 68.4 14.5 11.1 7.9 2021.0003 JAN 85.2 79.2 68.4 15.7 11.4 7.7 2021.0837 FEB 88.2 80.9 68.4 16.1 11.6 7.7 2021.1670 MAR 90.2 82.9 68.4 16.3 11.8 7.6 2021.2503 APR 92.2 85.1 68.3 16.8 12.0 7.6 2021.3337 MAY 95.6 87.3 68.6 18.0 12.3 7.6 2021.4170 JUN 99.1 89.9 68.7 18.9 12.6 7.7 2021.5003 JUL 103.5 92.6 68.9 19.1 12.7 7.7 2021.5837 AUG 108.5 95.4 69.2 19.2 12.9 7.8 2021.6670 SEP 112.0 98.2 69.2 19.0 13.1 7.7 2021.7503 OCT 116.5 101.0 69.5 18.6 13.1 7.7 2021.8337 NOV 120.8 103.9 69.9 18.5 13.2 7.8 2021.9170 DEC 124.1 107.0 70.6 18.9 13.4 8.0 2022.0003 JAN 126.7 110.1 70.9 18.8 13.5 8.2 2022.0837 FEB 129.2 113.2 71.3 17.8 13.5 8.6 2022.1670 MAR 133.3 116.5 71.5 17.9 13.7 8.7 2022.2503 APR 138.2 119.7 72.1 18.5 13.9 8.7 2022.3337 MAY 142.8 122.9 72.9 19.1 14.2 9.0 2022.4170 JUN 148.3 125.7 73.3 19.6 14.6 9.4 2022.5003 JUL 152.9 128.2 74.1 20.3 14.9 9.6 2022.5837 AUG 157.7 130.5 74.7 20.3 15.1 9.6 2022.6670 SEP 163.7 132.6 75.1 20.3 15.1 9.8 2022.7503 OCT 169.4 135.1 75.6 20.5 15.2 10.0 2022.8337 NOV 174.6 137.7 75.9 20.8 15.4 10.5 2022.9170 DEC 180.2 140.3 76.1 21.2 15.4 11.1 2023.0003 JAN 183.5 142.4 76.1 21.3 15.3 11.6 2023.0837 FEB 185.6 144.3 76.0 21.4 15.1 11.3 2023.1670 MAR 185.7 146.0 76.1 21.6 15.0 11.2 2023.2503 APR 185.2 147.7 76.6 22.0 15.0 10.7 2023.3337 MAY 184.2 149.0 76.9 22.8 14.9 10.2 2023.4170 JUN 184.6 149.9 77.6 22.5 14.7 9.9 2023.5003 JUL 187.3 150.8 78.9 21.3 14.5 10.1 2023.5837 AUG 190.1 151.2 79.7 20.6 14.3 10.1 2023.6670 SEP 191.7 151.4 80.6 20.1 14.2 10.3 2023.7503 OCT 191.8 151.7 82.2 19.6 14.1 10.6 2023.8337 NOV 191.4 151.9 83.8 19.5 14.0 10.6 2023.9170 DEC 189.8 152.0 85.6 19.3 14.0 10.5 2024.0003 JAN 186.5 151.2 86.4 19.1 14.2 10.5 2024.0837 FEB 182.2 149.7 87.8 18.9 14.6 10.5 2024.1670 MAR 177.4 148.7 89.5 18.9 14.7 10.3 2024.2503 APR 173.9 148.4 90.7 19.5 14.6 9.8 2024.3337 MAY 177.0 148.5 93.0 20.4 14.7 10.2 2024.4170 JUN 176.6 148.9 94.2 22.0 15.0 10.7 2024.5003 JUL 173.8 149.0 95.5 23.4 15.3 10.7 2024.5837 AUG 172.7 148.7 95.8 24.0 15.4 10.9 2024.6670 SEP 171.7 148.1 95.4 25.1 15.7 11.1 2024.7503 OCT 170.6 147.5 95.4 25.6 15.9 11.3 2024.8337 NOV 167.1 147.3 96.9 24.9 15.9 11.5 2024.9170 DEC 163.8 147.2 97.7 24.8 15.9 11.7 2025.0003 JAN 161.2 146.4 97.2 23.9 15.8 11.9 2025.0837 FEB 158.7 145.1 96.4 22.1 15.8 11.8 2025.1670 MAR 155.9 143.5 96.3 22.4 15.9 12.0 2025.2503 APR 155.7 141.8 96.8 23.1 16.0 11.8 2025.3337 MAY 156.4 140.1 96.3 23.1 16.0 11.1 2025.4170 JUN 154.9 138.8 95.5 22.6 16.0 10.8 2025.5003 JUL 151.2 137.4 96.1 22.0 15.8 10.8 2025.5837 AUG 147.1 135.6 97.1 21.9 15.8 10.8 2025.6670 SEP 144.2 133.7 96.2 22.7 16.1 10.8 2025.7503 OCT 144.9 132.2 94.5 23.7 16.5 10.8 2025.8337 NOV 142.3 130.9 93.8 23.9 16.7 10.8 2025.9170 DEC 137.0 129.5 93.6 23.9 17.0 10.7 2026.0003 JAN 134.3 127.8 91.7 23.9 17.1 10.6 2026.0837 FEB 134.9 125.9 88.3 23.5 17.2 10.3 2026.1670 MAR 134.0 124.6 87.9 22.5 17.2 10.5 2026.2503 APR 134.3 123.5 88.7 22.7 17.2 10.7 2026.3337 MAY 132.9 122.3 87.3 23.0 17.4 11.4 2026.4170 JUN 131.5 121.0 86.3 23.1 17.6 11.9 2026.5003 JUL 130.4 119.3 85.7 22.5 17.8 12.0 2026.5837 AUG 129.7 117.4 84.8 21.7 17.6 12.1 2026.6670 SEP 126.8 115.6 83.6 21.2 17.4 12.3 2026.7503 OCT 125.7 113.7 82.5 21.7 17.0 12.5 2026.8337 NOV 125.9 111.7 82.1 21.7 16.9 13.3 2026.9170 DEC 124.1 110.0 82.1 22.1 16.9 13.1 2027.0003 JAN 122.4 108.6 82.0 22.6 17.0 12.8 2027.0837 FEB 120.8 107.0 80.9 22.3 16.8 13.1 2027.1670 MAR 118.9 105.5 80.5 22.4 16.5 12.7 2027.2503 APR 116.4 104.0 80.6 22.7 16.2 12.5 2027.3337 MAY 115.2 102.5 80.0 22.9 15.8 12.1 2027.4170 JUN 114.2 100.9 79.1 23.5 15.6 11.2 2027.5003 JUL 111.9 99.4 77.7 24.1 15.4 10.5 2027.5837 AUG 108.1 98.2 75.6 24.8 15.3 10.7 2027.6670 SEP 106.6 97.1 74.5 25.3 15.3 10.8 2027.7503 OCT 105.0 96.1 74.0 25.6 15.3 10.6 2027.8337 NOV 104.3 95.2 73.6 25.4 15.3 10.8 2027.9170 DEC 102.5 94.2 73.4 24.9 15.2 11.0 2028.0003 JAN 100.8 92.9 73.0 24.0 15.0 11.1 2028.0837 FEB 99.1 91.7 72.7 23.0 14.9 11.3 2028.1670 MAR 98.3 90.7 71.9 22.5 15.0 11.2 2028.2503 APR 98.3 89.6 71.4 22.1 15.1 11.1 2028.3337 MAY 97.9 88.4 71.0 21.8 15.2 11.2 2028.4170 JUN 97.0 87.3 70.7 21.4 15.3 11.4 2028.5003 JUL 95.7 86.5 70.4 20.7 15.2 11.5 2028.5837 AUG 95.0 85.6 70.5 19.9 14.9 11.3 2028.6670 SEP 93.3 84.7 70.3 20.0 14.7 11.1 2028.7503 OCT 91.0 83.5 69.8 20.1 14.6 10.8 2028.8337 NOV 89.6 82.4 69.6 19.9 14.3 10.1 2028.9170 DEC 88.2 81.7 69.5 19.5 14.2 9.6 2029.0003 JAN 86.7 81.0 69.4 19.0 14.1 9.1 2029.0837 FEB 86.0 80.3 69.3 18.3 14.1 8.6 2029.1670 MAR 85.4 79.6 69.1 17.3 14.0 8.0 2029.2503 APR 84.3 78.9 68.8 17.4 13.8 7.5 2029.3337 MAY 82.9 78.2 68.5 17.5 13.7 7.6 2029.4170 JUN 81.8 77.5 68.3 17.6 13.7 7.8 2029.5003 JUL 81.3 77.0 68.4 17.5 13.6 8.3 2029.5837 AUG 81.0 76.5 68.4 17.7 13.5 8.6 2029.6670 SEP 80.8 75.9 68.5 18.1 13.4 8.5 2029.7503 OCT 79.4 75.4 68.4 17.9 13.2 8.6 2029.8337 NOV 78.0 74.9 68.4 17.6 12.9 8.5 2029.9170 DEC 77.4 74.2 68.3 17.3 12.6 8.5 2030.0003 JAN 76.8 73.5 68.0 16.3 12.2 8.4 2030.0837 FEB 75.8 72.8 67.8 14.8 11.8 8.4 2030.1670 MAR 75.6 72.3 67.6 13.8 11.4 8.3 2030.2503 APR 74.6 72.0 67.6 13.9 11.0 8.2 2030.3337 MAY 73.4 71.6 67.5 13.6 10.6 8.2 2030.4170 JUN 73.5 71.2 67.2 13.2 10.3 7.9 2030.5003 JUL 72.6 70.9 67.1 12.9 9.9 7.4 2030.5837 AUG 72.3 70.6 67.1 12.6 9.7 7.1 2030.6670 SEP 72.2 70.3 67.0 11.9 9.5 7.3 2030.7503 OCT 71.9 70.1 67.0 11.4 9.4 7.1