TABLE 3 ESTIMATES OF 13-MONTH SMOOTH SOLAR ACTIVITY FOR BALANCE OF CYCLE 25 WITH A MEAN CYCLE GIVEN FOR CYCLE 26 TIME 10.7 CM SOLAR FLUX (F10.7) GEOMAGNETIC INDEX (Ap) PERCENTILE PERCENTILE 95.0% 50% 5.0% 95.0% 50% 5.0% 2025.1670 MAR 178.2 174.6 170.6 16.1 14.8 13.3 2025.2503 APR 179.9 172.4 163.3 17.2 15.0 12.8 2025.3337 MAY 180.5 170.5 157.5 18.0 15.1 12.7 2025.4170 JUN 180.9 168.6 152.9 18.8 15.1 11.9 2025.5003 JUL 179.7 166.2 147.7 19.5 15.1 11.1 2025.5837 AUG 179.4 163.5 144.7 20.4 15.1 10.9 2025.6670 SEP 177.9 160.2 140.6 21.0 15.4 10.5 2025.7503 OCT 176.5 157.1 135.3 21.6 15.7 10.1 2025.8337 NOV 176.2 154.4 131.2 21.7 15.9 10.4 2025.9170 DEC 176.7 151.9 128.8 21.2 16.1 10.9 2026.0003 JAN 176.0 148.9 125.4 20.3 16.1 11.0 2026.0837 FEB 173.7 146.1 122.0 20.3 16.1 11.0 2026.1670 MAR 170.2 144.0 119.9 20.5 16.1 11.5 2026.2503 APR 166.5 142.1 118.4 20.9 16.1 11.9 2026.3337 MAY 163.6 139.9 116.9 21.5 16.2 11.9 2026.4170 JUN 160.7 137.4 115.1 21.7 16.4 11.8 2026.5003 JUL 157.4 134.4 113.2 21.2 16.4 12.1 2026.5837 AUG 151.3 131.4 111.9 20.7 16.3 12.7 2026.6670 SEP 146.7 128.9 110.4 21.6 16.2 12.9 2026.7503 OCT 145.6 126.4 107.8 22.0 16.0 12.9 2026.8337 NOV 144.9 123.9 104.2 21.9 16.0 12.5 2026.9170 DEC 143.0 121.8 101.7 22.1 16.0 12.2 2027.0003 JAN 139.9 119.7 100.5 22.5 16.1 12.1 2027.0837 FEB 136.4 117.4 98.9 22.3 16.1 12.2 2027.1670 MAR 134.1 115.0 96.8 22.3 15.9 11.7 2027.2503 APR 133.3 112.9 94.1 22.6 15.7 11.5 2027.3337 MAY 132.7 110.8 90.8 22.8 15.4 11.0 2027.4170 JUN 131.5 108.2 88.0 23.4 15.2 10.1 2027.5003 JUL 130.4 106.1 85.8 24.0 14.9 9.4 2027.5837 AUG 128.8 104.5 84.0 24.7 14.8 9.4 2027.6670 SEP 128.1 103.1 83.0 25.2 14.7 9.4 2027.7503 OCT 127.0 101.9 82.3 25.4 14.7 9.4 2027.8337 NOV 124.9 100.9 82.1 25.3 14.5 9.6 2027.9170 DEC 122.9 99.9 81.6 24.8 14.4 9.8 2028.0003 JAN 121.2 98.4 80.5 23.9 14.2 9.8 2028.0837 FEB 120.2 96.9 79.4 23.0 14.1 9.2 2028.1670 MAR 118.8 95.4 78.4 22.5 14.1 8.7 2028.2503 APR 115.9 93.9 77.9 22.1 14.2 8.0 2028.3337 MAY 113.3 92.3 77.5 21.8 14.3 7.4 2028.4170 JUN 110.6 91.0 77.3 21.4 14.4 7.3 2028.5003 JUL 108.0 89.9 77.0 20.8 14.4 7.7 2028.5837 AUG 106.4 88.8 76.5 19.9 14.2 8.1 2028.6670 SEP 104.6 87.3 76.0 20.1 14.1 8.4 2028.7503 OCT 102.2 85.8 75.2 20.3 13.9 8.4 2028.8337 NOV 99.6 84.5 74.2 20.0 13.7 8.4 2028.9170 DEC 97.8 83.5 73.8 19.6 13.6 8.3 2029.0003 JAN 96.6 82.6 73.3 19.0 13.6 8.3 2029.0837 FEB 95.5 81.7 72.8 18.3 13.6 8.4 2029.1670 MAR 93.9 81.0 72.6 17.4 13.5 8.1 2029.2503 APR 93.0 80.3 72.3 17.5 13.3 7.8 2029.3337 MAY 92.2 79.7 72.0 17.6 13.1 7.7 2029.4170 JUN 91.1 79.0 71.9 17.8 13.0 7.7 2029.5003 JUL 90.0 78.3 71.8 17.8 12.9 7.2 2029.5837 AUG 89.0 77.7 71.6 17.8 12.8 7.0 2029.6670 SEP 87.6 77.2 71.6 17.8 12.7 7.2 2029.7503 OCT 86.3 76.8 71.6 17.8 12.5 6.9 2029.8337 NOV 84.3 76.2 71.4 17.5 12.3 6.8 2029.9170 DEC 82.1 75.5 71.3 17.2 12.0 6.6 2030.0003 JAN 80.7 74.8 70.8 16.2 11.6 6.5 2030.0837 FEB 79.7 74.0 70.2 14.8 11.2 6.4 2030.1670 MAR 79.2 73.4 69.8 13.9 10.9 6.3 2030.2503 APR 78.8 73.0 69.6 14.0 10.5 6.3 2030.3337 MAY 78.5 72.6 69.6 13.7 10.2 6.3 2030.4170 JUN 78.3 72.2 69.4 13.2 9.8 6.1 2030.5003 JUL 77.4 71.9 68.9 12.9 9.5 5.9 2030.5837 AUG 76.2 71.6 68.6 12.6 9.3 5.8 2030.6670 SEP 75.2 71.3 68.3 11.9 9.1 5.7 2030.7503 OCT 74.8 71.2 68.1 11.4 8.9 5.2 2030.8337 NOV 74.4 71.0 68.2 11.3 8.7 4.9 2030.9170 DEC 74.3 70.9 68.1 11.2 8.7 4.9 2031.0003 JAN 74.3 70.9 68.0 11.4 8.7 4.6 2031.0837 FEB 74.9 71.1 68.0 11.7 8.9 4.6 2031.1670 MAR 75.7 71.4 68.0 11.8 9.0 4.5 2031.2503 APR 76.3 71.7 68.0 12.0 9.0 4.2 2031.3337 MAY 77.3 72.0 68.0 12.1 9.1 3.9 2031.4170 JUN 78.9 72.5 68.1 12.2 9.2 3.8 2031.5003 JUL 80.2 73.1 68.1 12.3 9.2 3.7 2031.5837 AUG 81.4 73.7 68.2 12.6 9.4 3.6 2031.6670 SEP 83.6 74.5 68.2 12.9 9.7 3.5 2031.7503 OCT 86.4 75.3 68.2 13.3 10.0 3.8 2031.8337 NOV 90.9 76.4 68.4 13.8 10.3 4.2 2031.9170 DEC 95.2 77.8 68.5 14.6 10.6 4.5 2032.0003 JAN 98.5 79.4 68.5 15.7 10.9 4.7 2032.0837 FEB 103.6 81.1 68.5 16.1 11.1 4.8 2032.1670 MAR 109.2 83.1 68.5 16.3 11.3 5.0 2032.2503 APR 115.2 85.2 68.4 16.9 11.4 5.1 2032.3337 MAY 122.0 87.5 68.6 18.0 11.6 5.3 2032.4170 JUN 130.1 89.9 68.7 18.9 11.9 5.4 2032.5003 JUL 136.6 92.5 69.0 19.1 12.1 5.6 2032.5837 AUG 141.4 95.3 69.3 19.2 12.3 5.8 2032.6670 SEP 145.9 98.1 69.4 19.0 12.6 6.0 2032.7503 OCT 150.4 100.9 69.6 18.6 12.7 6.1 2032.8337 NOV 155.4 103.7 70.1 18.5 12.7 6.1 2032.9170 DEC 160.9 106.7 70.8 18.9 12.8 6.1 2033.0003 JAN 166.3 109.8 71.0 18.8 12.9 6.3 2033.0837 FEB 171.1 113.0 71.4 17.8 13.0 6.5 2033.1670 MAR 177.2 116.2 71.7 17.9 13.2 6.7 2033.2503 APR 184.3 119.3 72.3 18.4 13.4 7.1 2033.3337 MAY 189.1 122.6 73.1 19.1 13.7 7.0 2033.4170 JUN 192.1 125.6 73.5 19.6 14.2 7.0 2033.5003 JUL 195.2 128.1 74.3 20.3 14.5 7.1 2033.5837 AUG 198.1 130.2 74.9 20.3 14.5 7.2 2033.6670 SEP 203.0 132.5 75.3 20.3 14.6 7.7 2033.7503 OCT 208.9 135.1 75.8 20.5 14.7 8.1 2033.8337 NOV 213.1 137.6 76.2 20.8 14.8 8.0 2033.9170 DEC 215.9 139.9 76.5 21.2 14.8 8.0 2034.0003 JAN 219.7 141.9 76.5 21.3 14.6 8.4 2034.0837 FEB 223.3 143.7 76.5 21.4 14.6 8.6 2034.1670 MAR 224.8 145.3 76.8 21.6 14.6 8.4 2034.2503 APR 225.6 146.8 77.3 22.0 14.5 8.4 2034.3337 MAY 228.0 147.9 77.8 22.7 14.4 8.6 2034.4170 JUN 230.3 148.7 78.5 22.4 14.1 8.6 2034.5003 JUL 233.0 149.3 79.8 21.3 13.8 8.5 2034.5837 AUG 235.9 149.6 80.6 20.6 13.7 8.3 2034.6670 SEP 237.0 149.9 81.6 20.1 13.6 8.0 2034.7503 OCT 234.9 150.2 83.1 19.7 13.5 7.6 2034.8337 NOV 232.6 150.3 84.6 19.6 13.5 7.5 2034.9170 DEC 233.6 150.3 86.2 19.3 13.5 7.8 2035.0003 JAN 234.0 149.6 87.0 19.1 13.7 7.7 2035.0837 FEB 231.8 148.5 88.2 18.9 13.9 7.6 2035.1670 MAR 228.8 147.7 89.8 18.9 14.0 7.5 2035.2503 APR 225.5 147.5 90.9 19.5 13.9 7.2 2035.3337 MAY 224.0 147.8 93.0 20.4 14.0 7.1 2035.4170 JUN 225.0 148.2 94.3 22.0 14.4 7.1 2035.5003 JUL 224.9 148.2 95.7 23.4 14.7 7.1 2035.5837 AUG 223.7 148.0 96.0 24.0 14.9 7.3 2035.6670 SEP 222.8 147.6 95.6 25.1 15.1 7.3 2035.7503 OCT 222.5 147.2 95.5 25.7 15.3 7.0 2035.8337 NOV 222.1 147.0 97.0 24.9 15.3 7.1 2035.9170 DEC 221.5 146.6 97.8 24.8 15.3 6.7 2036.0003 JAN 220.9 145.8 97.3 24.0 15.3 6.3 2036.0837 FEB 218.8 144.6 96.5 22.2 15.3 6.1 2036.1670 MAR 215.7 143.1 96.4 22.5 15.5 6.3 2036.2503 APR 213.2 141.4 96.9 23.2 15.7 6.5 2036.3337 MAY 210.6 140.0 96.4 23.2 15.7 6.7 2036.4170 JUN 206.4 138.7 95.7 22.7 15.7 7.1 2036.5003 JUL 203.6 137.2 96.3 22.0 15.6 7.6 2036.5837 AUG 202.2 135.5 97.2 21.9 15.7 7.7 2036.6670 SEP 198.4 133.5 96.3 22.7 15.9 8.1 2036.7503 OCT 194.6 131.8 94.6 23.6 16.2 8.7 2036.8337 NOV 192.8 130.4 93.8 23.8 16.4 8.9 2036.9170 DEC 191.1 129.2 93.6 23.8 16.6 9.3 2037.0003 JAN 187.6 127.5 91.8 23.8 16.6 9.7 2037.0837 FEB 183.5 125.7 88.4 23.4 16.6 10.1 2037.1670 MAR 179.5 124.4 88.0 22.5 16.5 10.5 2037.2503 APR 175.8 123.3 88.7 22.7 16.4 10.7 2037.3337 MAY 173.5 121.9 87.3 22.9 16.5 11.5 2037.4170 JUN 171.4 120.3 86.3 23.0 16.6 11.7 2037.5003 JUL 167.1 118.5 85.7 22.4 16.7 11.9 2037.5837 AUG 160.8 116.7 84.9 21.5 16.5 11.9 2037.6670 SEP 155.0 115.0 83.7 21.2 16.3 11.7 2037.7503 OCT 151.3 113.1 82.7 21.7 16.1 11.4 2037.8337 NOV 148.8 111.2 82.3 21.7 16.1 11.5 2037.9170 DEC 146.2 109.6 82.2 22.1 16.1 11.4 2038.0003 JAN 143.2 108.0 82.0 22.5 16.2 11.2 2038.0837 FEB 139.6 106.4 81.0 22.3 16.2 11.0 2038.1670 MAR 135.9 104.8 80.6 22.3 16.0 10.8 2038.2503 APR 132.4 103.4 80.6 22.7 15.8 10.7 2038.3337 MAY 128.4 101.8 80.0 22.9 15.5 10.6 2038.4170 JUN 123.3 100.2 79.1 23.4 15.3 10.3 2038.5003 JUL 119.4 98.7 77.7 24.0 15.0 10.1 2038.5837 AUG 118.6 97.5 75.7 24.7 14.9 10.1 2038.6670 SEP 118.7 96.3 74.6 25.3 14.8 10.1 2038.7503 OCT 119.2 95.2 74.1 25.4 14.8 10.5 2038.8337 NOV 119.5 94.3 73.8 25.3 14.7 10.4 2038.9170 DEC 118.8 93.3 73.5 24.8 14.5 10.2 2039.0003 JAN 117.3 92.1 73.1 23.9 14.3 10.0 2039.0837 FEB 115.7 91.0 72.7 23.0 14.1 9.4 2039.1670 MAR 113.5 90.0 72.0 22.5 14.2 8.8 2039.2503 APR 110.0 89.0 71.4 22.1 14.2 8.1 2039.3337 MAY 105.8 87.8 71.1 21.8 14.3 7.5 2039.4170 JUN 103.2 86.8 70.8 21.4 14.5 7.4 2039.5003 JUL 101.6 85.9 70.5 20.8 14.4 7.7 2039.5837 AUG 100.1 85.1 70.6 20.0 14.3 8.1 2039.6670 SEP 98.1 84.1 70.4 20.0 14.1 8.5 2039.7503 OCT 96.5 83.0 69.9 20.2 13.9 8.5 2039.8337 NOV 94.6 82.0 69.6 19.8 13.7 8.5 2039.9170 DEC 93.5 81.3 69.5 19.4 13.6 8.4 2040.0003 JAN 93.1 80.6 69.5 18.9 13.6 8.4 2040.0837 FEB 92.3 80.0 69.3 18.2 13.6 8.1 2040.1670 MAR 91.2 79.2 69.2 17.3 13.5 7.7 2040.2503 APR 90.3 78.5 68.8 17.3 13.3 7.1 2040.3337 MAY 89.5 77.8 68.6 17.4 13.2 6.8 2040.4170 JUN 88.4 77.2 68.4 17.5 13.1 6.6 2040.5003 JUL 87.4 76.6 68.4 17.5 12.9 6.5 2040.5837 AUG 86.6 76.1 68.5 17.7 12.9 6.6 2040.6670 SEP 85.2 75.6 68.5 18.0 12.7 6.5 2040.7503 OCT 83.9 75.1 68.5 17.9 12.6 6.4 2040.8337 NOV 82.0 74.6 68.4 17.6 12.3 6.4 2040.9170 DEC 79.9 73.9 68.3 17.3 12.0 6.2 2041.0003 JAN 78.4 73.2 68.1 16.3 11.7 6.1 2041.0837 FEB 77.5 72.6 67.8 14.9 11.2 6.0 2041.1670 MAR 77.0 72.1 67.7 13.8 10.9 6.1 2041.2503 APR 76.9 71.8 67.6 13.9 10.5 6.2 2041.3337 MAY 76.6 71.5 67.5 13.6 10.2 6.2 2041.4170 JUN 76.5 71.1 67.3 13.2 9.8 6.0 2041.5003 JUL 76.1 70.8 67.1 12.9 9.5 5.9 2041.5837 AUG 75.1 70.5 67.1 12.6 9.3 5.8 2041.6670 SEP 74.2 70.2 67.0 11.9 9.1 5.7 2041.7503 OCT 74.0 70.0 67.0 11.4 8.9 5.2