TABLE 3 ESTIMATES OF 13-MONTH SMOOTH SOLAR ACTIVITY FOR BALANCE OF CYCLE 23 CYCLE 24 AND BEGINNING OF CYCLE 25 TIME 10.7 CM SOLAR FLUX (F10.7) GEOMAGNETIC INDEX (Ap) PERCENTILE PERCENTILE 95.0% 50% 5.0% 95.0% 50% 5.0% 2008.1667 MAR 70.4 69.8 68.8 7.8 7.5 7.0 2008.2500 APR 71.6 70.0 67.7 8.2 7.4 6.7 2008.3333 MAY 72.8 70.2 66.5 8.7 7.5 6.5 2008.4167 JUN 73.8 70.3 65.7 9.1 7.6 6.0 2008.5000 JUL 74.9 70.5 64.9 9.4 7.8 5.8 2008.5833 AUG 75.9 70.8 64.1 10.1 7.9 5.9 2008.6667 SEP 77.1 71.3 63.4 11.3 8.3 6.3 2008.7500 OCT 78.9 71.9 62.8 13.1 8.8 6.9 2008.8333 NOV 80.8 72.5 62.1 14.3 9.2 7.5 2008.9167 DEC 82.7 73.3 61.6 15.0 9.6 7.6 2009.0000 JAN 84.8 74.3 60.9 15.8 10.2 7.7 2009.0833 FEB 87.1 75.3 60.1 16.2 10.5 7.7 2009.1667 MAR 89.9 76.5 58.9 16.4 10.7 7.7 2009.2500 APR 92.4 77.8 58.4 16.8 10.7 7.8 2009.3333 MAY 94.6 79.3 58.5 17.1 10.9 8.0 2009.4167 JUN 97.0 81.0 58.8 17.3 11.2 8.3 2009.5000 JUL 100.3 82.9 59.7 17.5 11.6 8.6 2009.5833 AUG 103.7 84.8 60.5 18.0 12.1 9.1 2009.6667 SEP 106.8 86.9 61.2 18.2 12.6 9.8 2009.7500 OCT 111.3 89.2 62.1 17.8 13.1 10.2 2009.8333 NOV 118.0 91.9 64.0 17.2 13.3 10.3 2009.9167 DEC 124.2 94.3 65.7 16.9 13.4 10.4 2010.0000 JAN 129.6 96.3 65.7 16.9 13.6 10.4 2010.0833 FEB 135.4 98.6 65.8 17.3 13.9 10.4 2010.1667 MAR 142.6 100.9 68.4 17.9 14.0 10.1 2010.2500 APR 149.9 103.1 72.1 18.4 14.1 10.0 2010.3333 MAY 156.9 105.5 75.0 18.7 14.1 9.8 2010.4167 JUN 165.2 108.2 77.7 18.8 13.7 9.0 2010.5000 JUL 170.6 112.0 79.3 19.0 13.8 9.1 2010.5833 AUG 176.0 115.7 80.9 19.2 13.9 9.3 2010.6667 SEP 181.3 119.4 82.4 19.5 14.0 9.4 2010.7500 OCT 186.6 123.0 84.0 19.7 14.0 9.5 2010.8333 NOV 191.7 126.6 85.5 19.9 14.1 9.6 2010.9167 DEC 196.7 130.1 87.0 20.1 14.2 9.8 2011.0000 JAN 201.6 133.5 88.4 20.3 14.2 9.9 2011.0833 FEB 206.3 136.8 89.8 20.5 14.3 10.0 2011.1667 MAR 210.9 139.9 91.1 20.7 14.4 10.1 2011.2500 APR 215.2 142.9 92.4 20.8 14.4 10.2 2011.3333 MAY 219.2 145.7 93.5 21.0 14.5 10.3 2011.4167 JUN 223.0 148.3 94.6 21.2 14.5 10.4 2011.5000 JUL 226.5 150.8 95.7 21.3 14.6 10.5 2011.5833 AUG 229.6 153.0 96.6 21.4 14.6 10.5 2011.6667 SEP 232.5 154.9 97.4 21.6 14.7 10.6 2011.7500 OCT 234.9 156.6 98.1 21.7 14.7 10.7 2011.8333 NOV 237.0 158.1 98.7 21.7 14.7 10.7 2011.9167 DEC 238.6 159.2 99.2 21.8 14.7 10.7 2012.0000 JAN 239.8 160.1 99.6 21.9 14.8 10.8 2012.0833 FEB 240.6 160.6 99.8 21.9 14.8 10.8 2012.1667 MAR 240.8 160.8 99.9 21.9 14.8 10.8 2012.2500 APR 237.9 159.6 98.5 20.6 14.9 11.5 2012.3333 MAY 233.7 157.8 97.8 20.2 15.0 11.8 2012.4167 JUN 229.9 156.0 96.7 19.7 15.1 11.7 2012.5000 JUL 228.6 154.7 95.4 19.4 15.3 11.9 2012.5833 AUG 228.6 153.6 93.8 19.2 15.6 12.1 2012.6667 SEP 227.1 152.7 92.6 19.0 15.7 11.6 2012.7500 OCT 225.2 151.7 91.8 19.0 15.7 10.9 2012.8333 NOV 224.4 150.4 91.2 18.9 15.7 10.8 2012.9167 DEC 223.6 148.9 90.3 19.0 15.7 10.8 2013.0000 JAN 222.8 147.2 89.3 19.2 15.8 10.8 2013.0833 FEB 221.6 145.3 88.6 19.8 15.9 10.8 2013.1667 MAR 217.7 143.4 87.7 20.4 16.1 10.9 2013.2500 APR 214.3 141.8 86.2 21.4 16.3 10.8 2013.3333 MAY 211.4 140.6 85.4 21.9 16.5 10.7 2013.4167 JUN 207.1 139.5 84.9 21.6 16.6 10.6 2013.5000 JUL 206.7 138.5 84.0 21.3 16.4 10.3 2013.5833 AUG 206.0 137.4 82.7 21.8 16.5 10.3 2013.6667 SEP 203.8 135.6 81.3 23.1 16.7 10.4 2013.7500 OCT 200.3 133.6 80.4 23.3 16.9 10.9 2013.8333 NOV 196.2 131.5 79.8 22.7 17.0 11.7 2013.9167 DEC 191.2 129.6 79.1 22.6 17.0 11.8 2014.0000 JAN 185.0 127.8 78.4 22.7 16.9 11.9 2014.0833 FEB 179.1 126.3 77.5 23.2 17.1 12.0 2014.1667 MAR 178.4 125.2 76.5 23.9 17.3 12.1 2014.2500 APR 177.7 123.7 75.5 23.9 17.2 12.5 2014.3333 MAY 175.3 121.6 74.6 23.9 17.1 13.3 2014.4167 JUN 171.4 119.5 73.6 23.3 17.0 13.7 2014.5000 JUL 166.1 117.5 72.7 21.6 16.8 13.3 2014.5833 AUG 161.9 115.9 72.3 21.8 16.6 12.8 2014.6667 SEP 160.4 114.4 72.0 21.8 16.4 12.7 2014.7500 OCT 159.3 112.9 71.6 21.5 16.4 12.5 2014.8333 NOV 157.5 111.4 71.4 21.1 16.4 12.4 2014.9167 DEC 154.7 109.9 71.5 20.5 16.4 12.2 2015.0000 JAN 150.5 108.3 71.4 19.9 16.1 11.9 2015.0833 FEB 144.9 106.7 71.2 20.1 16.0 11.9 2015.1667 MAR 138.7 104.8 70.9 21.6 15.9 11.7 2015.2500 APR 132.9 103.0 70.7 23.2 15.8 11.7 2015.3333 MAY 128.3 101.4 70.5 24.0 15.8 11.5 2015.4167 JUN 124.5 99.9 70.7 25.1 15.7 11.3 2015.5000 JUL 121.4 98.7 71.1 25.8 15.7 11.3 2015.5833 AUG 119.3 97.7 71.2 25.0 15.6 10.8 2015.6667 SEP 119.4 96.7 71.4 25.0 15.6 10.3 2015.7500 OCT 119.0 95.6 71.2 24.1 15.7 10.7 2015.8333 NOV 117.9 94.3 70.7 22.2 15.7 10.8 2015.9167 DEC 117.2 93.0 70.3 21.4 15.6 10.8 2016.0000 JAN 116.2 91.9 69.9 21.7 15.8 11.0 2016.0833 FEB 116.4 91.1 69.6 22.4 16.0 11.2 2016.1667 MAR 116.7 90.2 69.2 22.6 16.0 11.2 2016.2500 APR 116.8 89.2 69.0 22.5 16.1 11.0 2016.3333 MAY 116.6 88.2 68.7 22.7 16.3 11.0 2016.4167 JUN 115.9 87.1 68.2 22.9 16.6 11.3 2016.5000 JUL 114.8 86.1 68.0 23.4 16.8 11.2 2016.5833 AUG 113.1 85.1 67.8 24.1 16.9 11.2 2016.6667 SEP 109.9 84.2 67.7 24.8 17.0 11.8 2016.7500 OCT 104.9 83.2 67.6 25.4 16.9 12.2 2016.8333 NOV 99.4 82.3 67.6 25.6 16.7 12.1 2016.9167 DEC 98.8 81.3 67.5 25.4 16.4 12.0 2017.0000 JAN 99.6 80.6 67.3 24.7 16.0 12.2 2017.0833 FEB 100.2 80.0 67.2 23.6 15.6 12.3 2017.1667 MAR 98.7 79.4 67.2 22.8 15.2 12.2 2017.2500 APR 95.8 78.8 67.2 22.4 14.9 11.8 2017.3333 MAY 93.0 78.2 67.2 21.9 14.6 11.2 2017.4167 JUN 91.3 77.8 67.1 21.6 14.2 10.7 2017.5000 JUL 91.5 77.2 67.1 20.9 13.8 10.0 2017.5833 AUG 91.4 76.6 67.0 20.0 13.4 9.4 2017.6667 SEP 90.9 76.0 67.0 18.7 13.1 9.0 2017.7500 OCT 90.4 75.6 67.0 18.2 12.8 8.5 2017.8333 NOV 89.7 75.1 67.0 18.7 12.6 8.0 2017.9167 DEC 88.8 74.7 67.1 18.7 12.5 7.8 2018.0000 JAN 88.1 74.4 67.3 18.4 12.4 7.4 2018.0833 FEB 87.2 74.0 67.4 18.4 12.2 7.0 2018.1667 MAR 85.9 73.7 67.5 18.8 12.1 6.6 2018.2500 APR 84.4 73.2 67.6 18.9 12.0 6.5 2018.3333 MAY 82.3 72.7 67.7 18.8 12.0 6.4 2018.4167 JUN 80.0 72.3 67.7 18.4 11.9 6.6 2018.5000 JUL 77.7 71.9 68.0 17.5 11.8 6.9 2018.5833 AUG 76.9 71.7 68.0 16.5 11.7 7.2 2018.6667 SEP 76.5 71.5 68.0 16.3 11.6 7.4 2018.7500 OCT 75.8 71.4 68.0 16.6 11.6 7.5 2018.8333 NOV 76.0 71.3 67.9 16.9 11.6 7.5 2018.9167 DEC 76.0 71.2 67.9 17.2 11.6 7.7 2019.0000 JAN 76.3 71.2 67.7 17.3 11.6 7.7 2019.0833 FEB 76.8 71.3 67.6 17.7 11.5 7.6 2019.1667 MAR 77.8 71.5 67.7 18.0 11.4 7.6 2019.2500 APR 79.5 71.9 67.6 18.2 11.4 7.6 2019.3333 MAY 81.5 72.3 67.6 18.1 11.3 7.6 2019.4167 JUN 83.2 72.6 67.7 17.8 11.2 7.5 2019.5000 JUL 85.4 73.2 67.9 17.3 11.1 7.5 2019.5833 AUG 88.2 74.0 68.1 16.3 11.0 7.5 2019.6667 SEP 91.0 74.9 68.5 15.5 10.9 7.5 2019.7500 OCT 93.8 75.8 68.6 16.1 10.8 7.7 2019.8333 NOV 96.7 76.9 68.8 16.3 10.8 7.7 2019.9167 DEC 100.7 78.4 69.1 16.6 10.9 7.8 2020.0000 JAN 105.5 80.0 69.3 16.7 11.0 7.7 2020.0833 FEB 111.4 81.8 69.6 16.8 11.1 7.7 2020.1667 MAR 116.6 83.6 70.2 17.1 11.1 7.8 2020.2500 APR 120.6 85.6 71.1 17.3 11.1 8.0 2020.3333 MAY 123.8 87.7 71.8 17.3 11.2 8.3 2020.4167 JUN 126.5 89.8 72.5 17.4 11.5 8.6 2020.5000 JUL 130.1 92.1 73.7 17.6 11.7 9.0 2020.5833 AUG 133.5 94.4 74.2 17.5 12.0 8.8 2020.6667 SEP 136.2 96.7 74.5 16.9 12.2 8.7 2020.7500 OCT 141.6 99.5 74.8 16.2 12.4 8.9 2020.8333 NOV 147.9 102.3 75.1 16.0 12.5 9.0 2020.9167 DEC 153.4 104.8 75.3 16.0 12.7 9.0 2021.0000 JAN 157.1 107.3 75.2 16.1 12.9 8.8 2021.0833 FEB 159.2 109.6 75.2 16.7 13.0 8.4 2021.1667 MAR 162.0 111.9 75.3 17.1 13.0 8.2 2021.2500 APR 165.3 114.5 75.7 17.5 13.1 8.2 2021.3333 MAY 172.5 117.4 76.1 18.2 13.2 8.1 2021.4167 JUN 181.4 120.5 76.6 18.5 13.2 7.9 2021.5000 JUL 188.0 123.1 77.5 18.5 13.1 7.8 2021.5833 AUG 191.8 125.3 78.3 18.7 13.1 7.9 2021.6667 SEP 194.8 127.4 78.6 19.0 13.2 8.1 2021.7500 OCT 197.7 129.3 79.6 18.6 13.3 8.6 2021.8333 NOV 201.4 131.0 80.8 17.8 13.3 9.2 2021.9167 DEC 206.7 132.7 82.2 18.1 13.4 9.6 2022.0000 JAN 211.5 134.8 84.1 18.9 13.5 10.1 2022.0833 FEB 214.4 137.2 85.4 19.1 13.6 10.1 2022.1667 MAR 218.4 139.6 86.3 19.5 13.9 10.3 2022.2500 APR 223.8 142.2 88.1 20.5 14.1 10.4 2022.3333 MAY 227.1 144.8 90.0 20.2 14.1 10.6 2022.4167 JUN 228.9 146.9 91.1 20.4 14.1 10.2 2022.5000 JUL 230.4 148.9 93.3 20.7 14.1 10.2 2022.5833 AUG 231.8 150.9 95.7 21.1 14.2 9.9 2022.6667 SEP 234.4 152.8 97.5 21.4 14.2 9.8 2022.7500 OCT 237.7 154.7 98.7 21.4 14.4 10.5 2022.8333 NOV 239.4 156.3 98.8 21.6 14.5 10.9 2022.9167 DEC 238.3 157.5 98.2 21.9 14.7 10.9 2023.0000 JAN 237.2 158.9 97.8 22.4 14.9 11.0 2023.0833 FEB 238.5 160.7 99.1 22.9 15.1 11.2