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% 1999.6673 SEP 164.1 158.0 154.2 13.6 12.9 12.5 1999.7507 OCT 171.3 159.3 152.5 14.6 13.0 11.9 1999.8340 NOV 176.5 160.2 151.7 14.9 13.3 11.6 1999.9173 DEC 183.2 160.9 149.8 15.5 13.5 11.6 2000.0007 JAN 187.8 161.3 146.9 16.4 13.8 11.7 2000.0840 FEB 191.1 161.5 143.3 16.7 14.2 11.8 2000.1673 MAR 194.0 161.6 140.0 16.6 14.5 11.5 2000.2507 APR 196.1 161.4 137.2 16.6 14.6 11.2 2000.3340 MAY 200.4 161.3 134.8 16.9 14.6 10.9 2000.4173 JUN 201.1 160.4 134.1 17.5 14.7 10.6 2000.5007 JUL 196.7 158.6 133.4 18.2 14.9 10.3 2000.5840 AUG 192.4 157.2 130.5 18.5 14.9 9.8 2000.6673 SEP 191.7 156.2 127.3 18.1 14.8 9.0 2000.7507 OCT 192.7 155.8 125.8 17.7 14.6 8.4 2000.8340 NOV 193.2 155.7 125.9 18.0 14.6 8.3 2000.9173 DEC 193.2 155.4 125.3 18.4 14.6 8.3 2001.0007 JAN 192.1 154.8 125.5 19.1 14.5 7.9 2001.0840 FEB 189.9 154.2 123.8 19.1 14.3 7.6 2001.1673 MAR 185.9 153.6 120.1 18.5 14.1 7.8 2001.2507 APR 181.0 153.2 117.9 18.4 14.0 8.3 2001.3340 MAY 177.7 152.8 116.1 18.1 14.0 8.7 2001.4173 JUN 176.7 152.0 114.3 17.8 13.9 9.0 2001.5007 JUL 178.7 150.8 113.0 17.8 13.9 9.2 2001.5840 AUG 179.4 149.1 110.5 17.5 13.9 9.3 2001.6673 SEP 179.1 147.4 108.9 17.0 14.1 9.5 2001.7507 OCT 178.8 146.1 107.4 17.5 14.5 10.3 2001.8340 NOV 179.5 145.0 106.3 17.7 14.5 10.8 2001.9173 DEC 180.6 143.5 105.5 17.4 14.4 10.5 2002.0007 JAN 180.5 141.6 104.8 18.1 14.4 10.9 2002.0840 FEB 178.1 139.4 104.1 19.5 14.8 11.2 2002.1673 MAR 175.9 137.7 101.8 20.7 15.1 11.4 2002.2507 APR 175.6 136.2 100.3 21.3 15.3 11.7 2002.3340 MAY 174.7 134.6 98.6 22.3 15.5 11.9 2002.4173 JUN 172.7 132.6 95.7 22.8 15.7 11.7 2002.5007 JUL 169.5 130.7 92.9 22.1 15.8 11.8 2002.5840 AUG 165.9 129.2 91.7 22.2 15.8 11.7 2002.6673 SEP 162.4 127.9 91.5 21.5 15.7 11.5 2002.7507 OCT 160.5 126.6 91.5 19.6 15.7 11.3 2002.8340 NOV 159.3 125.2 91.3 19.1 15.7 11.3 2002.9173 DEC 156.2 123.3 90.8 19.7 15.9 11.4 2003.0007 JAN 150.9 121.0 90.1 19.9 15.9 11.6 2003.0840 FEB 146.2 118.9 88.9 19.7 15.8 11.3 2003.1673 MAR 143.7 116.7 87.6 19.9 15.6 11.3 2003.2507 APR 142.4 114.6 85.2 19.4 15.5 11.4 2003.3340 MAY 140.5 112.8 83.4 19.3 15.7 11.4 2003.4173 JUN 138.0 111.2 82.9 20.0 15.9 11.5 2003.5007 JUL 135.6 109.6 82.4 19.9 16.1 11.6 2003.5840 AUG 132.9 107.9 81.5 19.8 16.3 11.5 2003.6673 SEP 130.4 106.2 79.7 19.7 16.4 11.4 2003.7507 OCT 130.2 104.5 77.2 19.6 16.4 11.1 2003.8340 NOV 128.9 102.7 75.8 19.8 16.4 11.1 2003.9173 DEC 126.5 101.1 75.1 20.3 16.4 11.2 2004.0007 JAN 125.6 99.7 74.0 20.9 16.5 11.9 2004.0840 FEB 124.5 98.5 73.2 21.1 16.8 12.4 2004.1673 MAR 122.3 97.5 72.7 20.7 17.1 12.4 2004.2507 APR 120.3 96.7 72.6 21.1 17.0 12.5 2004.3340 MAY 118.9 95.7 72.0 21.9 16.9 12.4 2004.4173 JUN 118.3 94.4 71.3 22.3 16.7 12.5 2004.5007 JUL 117.1 93.2 70.8 22.1 16.7 13.3 2004.5840 AUG 114.8 91.9 70.4 21.8 16.8 12.8 2004.6673 SEP 111.5 90.6 70.5 22.2 16.9 12.5 2004.7507 OCT 108.0 89.2 70.7 21.9 16.8 12.3 2004.8340 NOV 104.9 88.2 71.0 21.8 16.6 11.9 2004.9173 DEC 103.9 87.4 71.0 22.0 16.3 11.5 2005.0007 JAN 102.6 86.5 70.9 22.0 15.9 10.8 2005.0840 FEB 101.3 85.4 71.2 22.4 15.6 9.7 2005.1673 MAR 99.2 84.2 71.2 22.8 15.4 8.6 2005.2507 APR 96.9 83.0 70.7 23.1 15.2 8.3 2005.3340 MAY 95.7 82.2 70.9 23.4 15.2 8.1 2005.4173 JUN 94.1 81.4 70.9 23.6 15.2 7.9 2005.5007 JUL 92.6 80.6 70.7 23.3 15.0 7.8 2005.5840 AUG 91.3 79.9 70.5 22.8 14.9 8.1 2005.6673 SEP 90.0 79.2 70.2 22.0 14.8 8.4 2005.7507 OCT 88.7 78.4 70.0 21.2 14.7 8.8 2005.8340 NOV 87.4 77.7 69.7 21.0 14.8 9.0 2005.9173 DEC 86.1 77.0 69.5 20.7 14.9 9.2 2006.0007 JAN 84.9 76.3 69.3 20.7 15.2 9.6 2006.0840 FEB 83.7 75.6 69.0 20.5 15.4 10.2 2006.1673 MAR 82.5 75.0 68.8 20.1 15.4 10.5 2006.2507 APR 81.4 74.4 68.6 20.0 15.2 10.7 2006.3340 MAY 80.3 73.8 68.4 20.2 15.0 11.2 2006.4173 JUN 79.3 73.2 68.2 20.2 14.9 11.9 2006.5007 JUL 78.3 72.6 68.0 19.9 14.7 11.7 2006.5840 AUG 77.4 72.1 67.8 19.4 14.6 11.6 2006.6673 SEP 76.6 71.7 67.7 18.8 14.6 11.4 2006.7507 OCT 75.9 71.3 67.5 18.1 14.7 11.2 2006.8340 NOV 75.2 70.9 67.4 18.0 14.7 10.5 2006.9173 DEC 74.6 70.6 67.3 17.9 14.5 10.3 2007.0007 JAN 74.1 70.3 67.2 17.8 14.4 10.2 2007.0840 FEB 73.8 70.1 67.1 17.4 14.3 10.2 2007.1673 MAR 73.5 69.9 67.0 17.1 14.3 10.3 2007.2507 APR 73.3 69.8 67.0 16.5 13.8 10.0 2007.3340 MAY 73.2 69.8 67.0 16.0 13.3 9.7 2007.4173 JUN 73.4 69.9 67.1 15.5 12.9 9.4 2007.5007 JUL 74.0 70.3 67.3 15.0 12.4 9.1 2007.5840 AUG 74.8 70.7 67.4 14.5 12.0 8.8 2007.6673 SEP 75.7 71.0 67.5 14.0 11.6 8.6 2007.7507 OCT 76.7 71.5 67.6 13.6 11.2 8.3 2007.8340 NOV 78.3 72.0 67.9 13.2 10.8 8.1 2007.9173 DEC 79.6 72.7 68.1 12.8 10.5 7.9 2008.0007 JAN 81.1 73.3 68.2 12.4 10.1 7.7 2008.0840 FEB 83.4 74.2 68.2 12.1 9.9 7.5 2008.1673 MAR 86.5 75.1 68.3 11.8 9.6 7.3 2008.2507 APR 91.3 76.3 68.3 11.5 9.4 7.2 2008.3340 MAY 95.8 77.7 68.3 11.4 9.2 7.1 2008.4173 JUN 99.3 79.1 68.6 11.2 9.1 7.0 2008.5007 JUL 104.6 80.8 68.6 11.1 9.0 6.9 2008.5840 AUG 110.7 82.8 68.7 11.1 9.0 6.9 2008.6673 SEP 116.6 84.9 68.9 11.3 9.1 6.9 2008.7507 OCT 124.0 87.2 68.9 11.6 9.3 7.1 2008.8340 NOV 132.5 89.6 69.0 11.7 9.4 7.4 2008.9173 DEC 139.0 92.2 69.4 11.9 9.5 7.5 2009.0007 JAN 143.6 95.0 69.8 12.0 9.6 7.5 2009.0840 FEB 147.9 97.8 70.1 12.1 9.6 7.3 2009.1673 MAR 152.2 100.6 70.8 12.2 9.7 7.2 2009.2507 APR 157.0 103.3 71.2 12.6 9.8 7.0 2009.3340 MAY 162.1 106.3 71.4 12.9 10.1 6.9 2009.4173 JUN 167.2 109.5 72.1 13.3 10.5 7.1 2009.5007 JUL 171.5 112.8 72.7 13.8 10.8 7.5 2009.5840 AUG 177.3 115.9 73.3 14.6 11.1 7.8 2009.6673 SEP 185.2 119.0 74.0 15.8 11.4 7.6 2009.7507 OCT 190.2 122.2 74.3 16.2 11.6 7.6 2009.8340 NOV 192.8 125.1 74.6 16.4 11.7 7.5 2009.9173 DEC 195.4 127.5 75.0 16.9 11.9 7.5 2010.0007 JAN 198.3 129.7 75.3 18.1 12.2 7.5 2010.0840 FEB 202.9 131.9 75.5 19.0 12.6 7.6 2010.1673 MAR 209.1 134.3 75.5 19.2 12.8 7.6 2010.2507 APR 213.2 136.8 75.1 19.3 13.0 7.7 2010.3340 MAY 215.9 139.1 74.9 19.1 13.2 7.6 2010.4173 JUN 220.4 141.2 75.2 18.7 13.3 7.6 2010.5007 JUL 225.0 143.1 75.5 18.6 13.3 7.7 2010.5840 AUG 227.3 144.9 76.3 19.0 13.5 7.9 2010.6673 SEP 228.4 146.5 77.5 18.9 13.6 8.1 2010.7507 OCT 230.3 147.9 78.2 17.9 13.6 8.5 2010.8340 NOV 232.4 148.8 79.1 18.0 13.8 8.6 2010.9173 DEC 235.4 149.7 80.7 18.6 14.1 8.6 2011.0007 JAN 238.7 150.1 82.6 19.2 14.3 8.9 2011.0840 FEB 240.3 150.5 84.7 19.7 14.8 9.3 2011.1673 MAR 238.7 150.8 85.9 20.4 15.1 9.5 2011.2507 APR 236.9 151.0 86.9 20.4 15.2 9.5 2011.3340 MAY 238.1 151.2 88.8 20.4 15.2 9.7 2011.4173 JUN 238.7 150.6 90.2 20.6 15.2 9.9 2011.5007 JUL 236.3 149.2 92.2 20.9 15.4 10.4 2011.5840 AUG 232.9 148.1 93.5 21.3 15.4 11.0 2011.6673 SEP 229.2 147.5 94.0 21.3 15.3 11.6 2011.7507 OCT 227.4 147.4 95.3 21.5 15.1 11.2 2011.8340 NOV 227.8 147.4 95.6 21.7 15.1 11.1 2011.9173 DEC 227.9 147.1 95.2 22.1 15.1 10.6 2012.0007 JAN 226.5 146.7 95.3 22.9 15.0 10.1 2012.0840 FEB 224.8 146.3 96.8 22.6 14.7 9.8 2012.1673 MAR 224.3 145.7 97.5 21.4 14.4 10.0 2012.2507 APR 224.2 145.2 97.1 20.7 14.3 10.0 2012.3340 MAY 223.6 144.8 96.3 20.1 14.2 10.2 2012.4173 JUN 222.6 144.0 96.3 19.7 14.1 10.5 2012.5007 JUL 220.3 143.0 96.8 19.6 14.1 10.5 2012.5840 AUG 216.8 141.4 95.9 19.4 14.1 10.4 2012.6673 SEP 213.9 139.8 95.4 19.2 14.4 10.4 2012.7507 OCT 211.1 138.6 96.2 19.0 14.7 10.4 2012.8340 NOV 207.6 137.6 97.2 19.0 14.9 10.2 2012.9173 DEC 206.6 136.3 96.2 19.5 14.8 9.8 2013.0007 JAN 204.5 134.6 94.6 20.5 14.9 10.1 2013.0840 FEB 201.1 132.8 93.9 22.1 15.3 10.6 2013.1673 MAR 197.5 131.4 93.6 23.5 15.6 10.6 2013.2507 APR 195.2 130.3 91.9 24.1 15.8 10.8 2013.3340 MAY 193.4 128.9 88.5 25.3 16.1 10.9 2013.4173 JUN 189.6 127.1 87.7 25.8 16.3 11.1 2013.5007 JUL 185.1 125.5 88.8 25.0 16.3 11.4 2013.5840 AUG 180.7 124.2 88.3 24.9 16.2 11.6 2013.6673 SEP 176.8 123.1 87.0 24.1 16.2 11.7 2013.7507 OCT 174.6 122.0 86.0 22.2 16.1 11.7 2013.8340 NOV 172.7 120.8 85.7 22.5 16.2 11.9 2013.9173 DEC 168.6 119.2 84.8 23.2 16.3 11.7 2014.0007 JAN 162.0 117.2 83.5 23.3 16.3 10.9 2014.0840 FEB 156.1 115.4 82.5 22.8 16.1 10.6 2014.1673 MAR 152.5 113.5 81.9 22.1 15.9 10.7 2014.2507 APR 150.3 111.5 81.9 22.0 15.9 10.7 2014.3340 MAY 148.0 109.8 81.6 22.9 16.1 10.6 2014.4173 JUN 145.1 108.3 80.4 23.8 16.4 10.7 2014.5007 JUL 142.0 106.9 80.5 24.0 16.6 10.7 2014.5840 AUG 138.4 105.4 80.2 24.0 16.8 10.6 2014.6673 SEP 134.5 103.9 79.5 24.0 16.9 10.5 2014.7507 OCT 130.1 102.4 79.0 23.6 16.9 10.2 2014.8340 NOV 124.1 100.8 78.2 22.7 16.9 10.3 2014.9173 DEC 119.1 99.3 77.1 22.9 16.8 10.5 2015.0007 JAN 118.2 98.0 75.4 23.1 16.9 11.3 2015.0840 FEB 118.7 96.9 74.3 23.2 17.2 11.8 2015.1673 MAR 119.3 95.9 73.6 22.6 17.3 11.9 2015.2507 APR 119.6 95.0 72.8 21.6 17.2 12.1 2015.3340 MAY 118.8 94.0 71.8 21.3 17.1 12.2 2015.4173 JUN 117.4 92.9 71.3 21.8 16.9 12.4 2015.5007 JUL 116.0 91.8 70.8 21.8 16.7 13.2 2015.5840 AUG 113.9 90.7 70.4 22.2 16.8 13.0 2015.6673 SEP 110.2 89.5 70.3 22.6 16.9 12.7 2015.7507 OCT 105.1 88.2 70.4 22.4 16.9 13.0 2015.8340 NOV 102.7 87.3 70.2 22.4 16.7 12.7 2015.9173 DEC 101.7 86.6 70.1 22.8 16.5 12.4 2016.0007 JAN 100.2 85.8 70.2 23.0 16.1 12.0 2016.0840 FEB 98.1 84.7 70.1 23.6 15.8 11.1 2016.1673 MAR 96.3 83.6 70.3 24.2 15.6 10.4 2016.2507 APR 94.5 82.5 69.8 25.0 15.5 10.5 2016.3340 MAY 93.4 81.8 69.6 25.5 15.5 10.6 2016.4173 JUN 92.1 81.0 69.4 25.7 15.5 10.5 2016.5007 JUL 91.7 80.3 69.3 25.6 15.4 10.6 2016.5840 AUG 91.1 79.5 69.0 25.0 15.3 10.9 2016.6673 SEP 90.5 78.8 68.7 24.1 15.1 11.0 2016.7507 OCT 89.8 78.1 68.4 23.1 14.9 11.2 2016.8340 NOV 88.9 77.5 68.3 22.6 15.0 11.1 2016.9173 DEC 88.0 77.0 68.3 22.2 15.2 11.0 2017.0007 JAN 87.1 76.4 68.2 21.9 15.4 11.1 2017.0840 FEB 85.8 75.9 68.0 21.5 15.5 11.3 2017.1673 MAR 84.4 75.4 67.7 20.8 15.5 11.4 2017.2507 APR 82.3 74.8 67.5 20.0 15.3 11.4 2017.3340 MAY 79.9 74.2 67.6 20.1 15.1 11.7 2017.4173 JUN 78.4 73.5 67.4 20.2 14.9 11.9 2017.5007 JUL 77.5 72.9 67.3 19.9 14.7 11.6 2017.5840 AUG 77.0 72.4 67.2 19.5 14.6 11.5 2017.6673 SEP 76.9 72.0 67.2 19.0 14.6 11.1 2017.7507 OCT 76.7 71.6 67.2 18.2 14.6 10.6 2017.8340 NOV 76.5 71.3 67.1 17.3 14.5 9.8 2017.9173 DEC 76.2 71.0 67.1 17.4 14.4 9.4 2018.0007 JAN 75.2 70.7 67.0 17.5 14.3 9.3 2018.0840 FEB 74.2 70.4 67.0 17.6 14.2 9.3 2018.1673 MAR 74.0 70.1 67.0 17.6 14.1 9.3