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% 2019.9173 DEC 69.7 69.5 69.3 5.7 5.5 5.2 2020.0007 JAN 70.2 69.8 69.2 5.9 5.6 5.0 2020.0840 FEB 71.1 70.1 69.2 6.0 5.6 5.0 2020.1673 MAR 72.1 70.5 69.4 6.0 5.5 4.9 2020.2507 APR 73.2 70.9 69.4 6.1 5.6 4.9 2020.3340 MAY 74.9 71.4 69.4 6.2 5.6 4.8 2020.4173 JUN 76.1 72.0 69.2 6.6 5.6 4.5 2020.5007 JUL 77.3 72.7 69.3 7.1 5.6 4.3 2020.5840 AUG 79.4 73.5 69.5 7.2 5.6 4.1 2020.6673 SEP 82.0 74.4 69.4 7.4 5.8 4.1 2020.7507 OCT 86.1 75.4 69.4 7.5 6.0 4.2 2020.8340 NOV 90.0 76.7 69.3 7.6 6.0 4.4 2020.9173 DEC 93.1 78.1 69.0 7.5 5.9 4.1 2021.0007 JAN 97.7 79.7 68.9 7.5 5.8 3.8 2021.0840 FEB 102.9 81.4 68.8 7.5 5.8 3.7 2021.1673 MAR 108.2 83.4 68.2 8.0 5.7 3.2 2021.2507 APR 114.6 85.4 67.7 8.9 5.8 3.0 2021.3340 MAY 122.0 87.6 67.5 9.8 6.1 3.0 2021.4173 JUN 127.8 89.9 67.8 10.0 6.2 3.0 2021.5007 JUL 131.9 92.5 68.6 9.9 6.4 3.0 2021.5840 AUG 135.7 95.1 68.9 9.4 6.4 3.0 2021.6673 SEP 139.6 97.7 69.0 8.8 6.4 3.2 2021.7507 OCT 144.0 100.3 69.8 8.2 6.3 3.4 2021.8340 NOV 149.3 103.1 70.9 8.4 6.4 3.5 2021.9173 DEC 155.9 106.0 71.3 9.3 6.6 3.9 2022.0007 JAN 162.4 108.9 72.1 10.5 7.0 4.6 2022.0840 FEB 170.1 111.8 73.3 10.9 7.5 5.2 2022.1673 MAR 177.0 114.7 74.6 10.8 7.9 5.4 2022.2507 APR 181.5 117.8 76.3 11.0 8.2 5.7 2022.3340 MAY 183.7 120.7 77.6 11.6 8.4 5.4 2022.4173 JUN 185.3 123.1 79.3 12.2 8.5 4.9 2022.5007 JUL 187.8 125.2 80.6 12.4 8.7 4.9 2022.5840 AUG 192.5 127.3 81.4 12.9 9.0 4.9 2022.6673 SEP 198.7 129.7 82.2 13.7 9.4 5.1 2022.7507 OCT 203.4 132.0 81.7 14.4 9.6 4.8 2022.8340 NOV 206.5 134.2 81.8 14.7 9.7 4.4 2022.9173 DEC 210.5 136.1 82.3 14.6 10.0 4.1 2023.0007 JAN 214.7 137.8 82.5 14.2 10.3 4.0 2023.0840 FEB 216.9 139.4 83.6 14.0 10.3 3.9 2023.1673 MAR 218.3 140.8 85.9 14.3 10.2 3.9 2023.2507 APR 220.4 141.9 87.1 15.1 10.1 3.6 2023.3340 MAY 221.9 142.7 86.5 15.3 10.1 3.5 2023.4173 JUN 223.8 143.4 85.3 15.0 10.3 4.1 2023.5007 JUL 226.3 143.7 85.1 14.9 10.5 4.7 2023.5840 AUG 227.5 143.9 85.7 14.5 10.5 5.0 2023.6673 SEP 227.3 144.3 86.8 13.9 10.3 5.0 2023.7507 OCT 226.7 144.5 88.7 13.7 10.2 5.1 2023.8340 NOV 227.4 144.6 90.7 13.8 10.3 5.2 2023.9173 DEC 227.1 144.1 92.0 13.5 10.2 5.1 2024.0007 JAN 224.1 143.0 92.9 13.3 10.0 5.4 2024.0840 FEB 220.6 142.4 93.7 12.9 9.7 5.7 2024.1673 MAR 217.0 142.1 94.5 12.9 9.3 5.6 2024.2507 APR 215.8 142.4 95.5 13.1 9.1 5.5 2024.3340 MAY 215.9 142.8 96.8 14.3 9.2 5.3 2024.4173 JUN 215.5 142.8 98.2 15.2 9.2 5.2 2024.5007 JUL 213.8 142.7 99.1 15.7 9.3 5.6 2024.5840 AUG 211.7 142.4 99.5 16.6 9.4 5.7 2024.6673 SEP 210.2 142.0 99.9 16.8 9.4 5.6 2024.7507 OCT 209.4 141.9 99.3 16.3 9.5 5.8 2024.8340 NOV 209.2 141.6 98.4 16.3 9.7 6.0 2024.9173 DEC 208.4 140.9 98.2 15.4 9.6 6.1 2025.0007 JAN 206.6 139.8 98.6 13.8 9.5 5.8 2025.0840 FEB 203.7 138.3 98.5 13.8 9.7 5.7 2025.1673 MAR 201.3 136.7 98.2 14.2 10.0 5.7 2025.2507 APR 198.5 135.2 97.0 14.4 10.2 6.0 2025.3340 MAY 194.3 134.0 96.4 15.2 10.5 6.6 2025.4173 JUN 190.5 132.6 96.5 15.7 10.8 6.9 2025.5007 JUL 186.4 131.0 96.1 16.3 10.6 6.7 2025.5840 AUG 182.3 129.2 96.1 16.6 10.6 6.9 2025.6673 SEP 179.5 127.8 96.4 17.0 10.8 7.3 2025.7507 OCT 176.7 126.6 96.0 17.0 10.9 7.1 2025.8340 NOV 174.1 125.6 96.0 16.3 10.9 6.9 2025.9173 DEC 170.8 124.1 96.2 15.3 10.8 6.8 2026.0007 JAN 167.1 122.3 94.9 14.0 10.9 6.7 2026.0840 FEB 164.5 121.2 94.2 13.5 11.3 7.1 2026.1673 MAR 162.2 120.3 92.6 14.3 11.7 7.6 2026.2507 APR 160.0 119.0 90.6 15.0 12.0 8.5 2026.3340 MAY 156.6 117.5 90.0 15.3 12.2 8.2 2026.4173 JUN 151.9 115.8 89.8 14.9 12.4 8.5 2026.5007 JUL 147.2 114.2 88.9 15.9 12.6 9.0 2026.5840 AUG 142.9 112.7 87.8 17.3 12.7 9.3 2026.6673 SEP 138.9 110.8 86.5 18.1 12.8 9.9 2026.7507 OCT 135.2 108.9 85.5 18.4 13.0 9.3 2026.8340 NOV 132.7 107.2 85.2 18.3 13.3 9.2 2026.9173 DEC 130.1 105.6 85.1 18.4 13.5 8.9 2027.0007 JAN 127.0 104.0 84.6 18.3 13.6 8.5 2027.0840 FEB 126.1 102.5 84.6 18.5 13.5 8.4 2027.1673 MAR 126.2 101.2 84.2 18.9 13.4 8.3 2027.2507 APR 126.1 99.8 82.8 19.2 13.2 8.0 2027.3340 MAY 125.8 98.3 81.0 19.7 12.9 7.0 2027.4173 JUN 125.3 97.0 80.0 20.0 12.4 6.0 2027.5007 JUL 124.1 95.8 78.8 20.3 12.0 5.6 2027.5840 AUG 123.3 94.6 77.9 20.6 11.8 5.5 2027.6673 SEP 122.3 93.6 77.4 20.8 11.7 5.4 2027.7507 OCT 120.2 92.7 77.2 20.6 11.5 5.4 2027.8340 NOV 118.0 91.8 76.6 19.9 11.3 5.3 2027.9173 DEC 116.4 90.7 75.7 18.9 11.0 5.5 2028.0007 JAN 115.6 89.7 74.6 18.2 11.0 5.8 2028.0840 FEB 114.6 88.9 73.7 18.0 11.2 5.9 2028.1673 MAR 112.1 88.0 73.3 17.8 11.4 5.4 2028.2507 APR 108.6 86.9 73.1 17.7 11.7 4.9 2028.3340 MAY 106.4 85.9 72.8 17.6 12.0 5.0 2028.4173 JUN 104.3 85.1 72.5 18.0 12.2 5.5 2028.5007 JUL 102.7 84.3 72.3 18.4 12.2 6.1 2028.5840 AUG 101.2 83.4 72.2 18.7 12.1 6.5 2028.6673 SEP 99.1 82.4 71.8 18.8 12.0 6.5 2028.7507 OCT 96.8 81.4 71.5 18.6 12.0 6.7 2028.8340 NOV 95.8 80.7 71.4 18.4 12.1 6.8 2028.9173 DEC 95.2 80.1 71.2 18.1 12.5 7.2 2029.0007 JAN 93.8 79.5 71.1 17.6 12.7 7.5 2029.0840 FEB 91.7 78.7 70.8 16.7 12.7 7.5 2029.1673 MAR 89.9 78.0 70.4 16.9 12.5 7.4 2029.2507 APR 88.4 77.3 70.1 16.9 12.1 7.1 2029.3340 MAY 86.9 76.6 70.0 16.9 11.8 6.7 2029.4173 JUN 85.8 76.1 69.9 16.9 11.8 6.2 2029.5007 JUL 85.1 75.6 69.9 17.2 11.8 6.1 2029.5840 AUG 83.8 75.2 69.7 17.6 12.0 6.5 2029.6673 SEP 82.1 74.7 69.4 17.6 11.9 6.6 2029.7507 OCT 80.1 74.2 69.4 17.3 11.7 6.5 2029.8340 NOV 79.2 73.5 69.2 17.0 11.5 6.5 2029.9173 DEC 78.1 72.9 68.9 15.9 11.0 6.4 2030.0007 JAN 77.1 72.3 68.5 14.4 10.3 6.4 2030.0840 FEB 76.5 71.9 68.2 13.1 9.8 6.3 2030.1673 MAR 76.3 71.6 68.1 13.1 9.4 6.1 2030.2507 APR 76.0 71.2 68.0 12.8 9.1 6.0 2030.3340 MAY 75.6 70.9 67.9 12.5 8.9 5.9 2030.4173 JUN 74.9 70.6 67.5 12.3 8.7 5.7 2030.5007 JUL 73.9 70.3 67.3 12.0 8.5 5.3 2030.5840 AUG 72.8 70.0 67.1 11.2 8.1 4.7 2030.6673 SEP 72.5 69.8 66.9 10.7 7.9 4.2 2030.7507 OCT 72.4 69.6 67.0 10.5 7.8 4.0 2030.8340 NOV 72.4 69.6 67.0 10.6 7.9 4.0 2030.9173 DEC 72.6 69.8 67.0 10.8 8.0 3.9 2031.0007 JAN 73.4 70.1 67.0 11.2 8.2 3.9 2031.0840 FEB 74.3 70.5 67.2 11.4 8.4 3.9 2031.1673 MAR 75.1 70.9 67.2 11.6 8.5 3.6 2031.2507 APR 76.3 71.3 67.4 11.8 8.6 3.5 2031.3340 MAY 78.0 71.9 67.6 11.9 8.8 3.4 2031.4173 JUN 79.5 72.6 67.7 12.1 8.9 3.4 2031.5007 JUL 80.9 73.4 67.8 12.4 9.2 3.3 2031.5840 AUG 83.2 74.2 68.0 12.8 9.5 3.4 2031.6673 SEP 86.2 75.2 68.1 13.2 9.9 3.8 2031.7507 OCT 90.8 76.4 68.4 13.8 10.4 4.2 2031.8340 NOV 95.1 77.8 68.5 14.6 10.6 4.5 2031.9173 DEC 98.5 79.4 68.5 15.7 10.9 4.6 2032.0007 JAN 103.6 81.1 68.5 16.1 11.1 4.8 2032.0840 FEB 109.2 83.1 68.5 16.3 11.3 5.0 2032.1673 MAR 115.2 85.2 68.4 16.9 11.4 5.0 2032.2507 APR 122.0 87.5 68.6 18.0 11.6 5.2 2032.3340 MAY 130.1 89.9 68.7 18.9 11.9 5.4 2032.4173 JUN 136.6 92.5 69.0 19.1 12.1 5.6 2032.5007 JUL 141.4 95.3 69.3 19.2 12.3 5.8 2032.5840 AUG 145.9 98.1 69.4 19.0 12.6 6.0 2032.6673 SEP 150.4 100.8 69.6 18.6 12.7 6.1 2032.7507 OCT 155.4 103.6 70.1 18.5 12.7 6.1 2032.8340 NOV 160.9 106.7 70.8 18.9 12.8 6.1 2032.9173 DEC 166.3 109.8 71.0 18.8 12.9 6.3 2033.0007 JAN 171.1 113.0 71.4 17.8 13.0 6.5 2033.0840 FEB 177.2 116.2 71.7 17.9 13.2 6.7 2033.1673 MAR 184.3 119.2 72.3 18.4 13.4 7.0 2033.2507 APR 189.1 122.5 73.1 19.1 13.7 7.0 2033.3340 MAY 192.1 125.6 73.5 19.6 14.2 7.0 2033.4173 JUN 195.2 128.0 74.3 20.3 14.5 7.0 2033.5007 JUL 198.1 130.2 74.9 20.3 14.5 7.2 2033.5840 AUG 203.0 132.5 75.3 20.3 14.5 7.6 2033.6673 SEP 208.8 135.1 75.9 20.5 14.6 8.0 2033.7507 OCT 213.0 137.6 76.2 20.8 14.8 8.0 2033.8340 NOV 215.9 139.9 76.5 21.2 14.8 8.0 2033.9173 DEC 219.7 141.8 76.5 21.3 14.6 8.3 2034.0007 JAN 223.3 143.7 76.5 21.4 14.6 8.6 2034.0840 FEB 224.8 145.3 76.8 21.6 14.6 8.5 2034.1673 MAR 225.6 146.8 77.3 22.0 14.5 8.4 2034.2507 APR 228.0 148.0 77.8 22.7 14.4 8.6 2034.3340 MAY 230.3 148.7 78.5 22.4 14.1 8.6 2034.4173 JUN 233.0 149.3 79.8 21.3 13.8 8.6 2034.5007 JUL 235.9 149.6 80.6 20.6 13.7 8.4 2034.5840 AUG 237.0 149.9 81.6 20.1 13.6 8.1 2034.6673 SEP 234.9 150.2 83.1 19.7 13.5 7.7 2034.7507 OCT 232.6 150.3 84.6 19.6 13.5 7.5 2034.8340 NOV 233.6 150.3 86.2 19.3 13.5 7.8 2034.9173 DEC 234.0 149.6 87.0 19.1 13.7 7.8 2035.0007 JAN 231.8 148.5 88.2 18.9 13.9 7.6 2035.0840 FEB 228.8 147.7 89.8 18.9 14.0 7.5 2035.1673 MAR 225.5 147.5 90.9 19.5 13.9 7.3 2035.2507 APR 224.0 147.8 93.0 20.4 14.0 7.1 2035.3340 MAY 225.0 148.1 94.3 22.0 14.4 7.1 2035.4173 JUN 224.9 148.1 95.7 23.4 14.6 7.0 2035.5007 JUL 223.7 147.9 96.0 24.0 14.8 7.2 2035.5840 AUG 222.7 147.5 95.6 25.1 15.1 7.3 2035.6673 SEP 222.5 147.1 95.5 25.7 15.3 7.1 2035.7507 OCT 222.1 147.0 97.0 24.9 15.3 7.1 2035.8340 NOV 221.5 146.6 97.8 24.8 15.4 6.9 2035.9173 DEC 220.9 145.8 97.3 24.0 15.3 6.4 2036.0007 JAN 218.8 144.6 96.5 22.2 15.3 6.1 2036.0840 FEB 215.7 143.0 96.4 22.5 15.5 6.2 2036.1673 MAR 213.2 141.4 96.9 23.2 15.6 6.4 2036.2507 APR 210.6 140.0 96.4 23.2 15.7 6.6 2036.3340 MAY 206.4 138.7 95.7 22.7 15.7 6.9 2036.4173 JUN 203.6 137.3 96.3 22.0 15.6 7.4 2036.5007 JUL 202.2 135.5 97.2 21.9 15.7 7.6 2036.5840 AUG 198.4 133.6 96.3 22.7 15.9 7.9 2036.6673 SEP 194.7 131.8 94.6 23.7 16.2 8.4 2036.7507 OCT 192.8 130.5 93.8 23.9 16.4 8.7 2036.8340 NOV 191.1 129.2 93.6 23.8 16.6 9.1 2036.9173 DEC 187.6 127.6 91.8 23.8 16.6 9.5 2037.0007 JAN 183.5 125.7 88.5 23.4 16.5 9.9 2037.0840 FEB 179.5 124.5 88.0 22.5 16.5 10.3 2037.1673 MAR 175.8 123.4 88.7 22.7 16.4 10.7 2037.2507 APR 173.5 122.0 87.3 23.0 16.5 11.2 2037.3340 MAY 171.4 120.4 86.3 23.0 16.6 11.6 2037.4173 JUN 167.1 118.6 85.7 22.4 16.7 11.8 2037.5007 JUL 160.8 116.8 84.9 21.5 16.5 11.9 2037.5840 AUG 155.0 115.1 83.7 21.2 16.4 11.8 2037.6673 SEP 151.3 113.2 82.7 21.7 16.2 11.5 2037.7507 OCT 148.8 111.3 82.3 21.7 16.0 11.4 2037.8340 NOV 146.2 109.6 82.2 22.1 16.1 11.5 2037.9173 DEC 143.2 108.1 82.0 22.5 16.2 11.3 2038.0007 JAN 139.6 106.5 81.0 22.3 16.2 11.1 2038.0840 FEB 135.9 104.9 80.6 22.3 16.0 10.9 2038.1673 MAR 132.4 103.4 80.6 22.7 15.8 10.7 2038.2507 APR 128.4 101.9 80.0 22.9 15.5 10.7 2038.3340 MAY 123.3 100.2 79.1 23.4 15.3 10.5 2038.4173 JUN 119.4 98.8 77.7 24.0 15.1 10.2 2038.5007 JUL 118.5 97.5 75.6 24.7 14.9 10.1 2038.5840 AUG 118.7 96.3 74.6 25.3 14.8 10.0 2038.6673 SEP 119.2 95.2 74.1 25.5 14.8 10.2 2038.7507 OCT 119.5 94.3 73.8 25.3 14.7 10.5 2038.8340 NOV 118.8 93.3 73.5 24.8 14.5 10.3 2038.9173 DEC 117.3 92.1 73.1 23.9 14.3 10.0 2039.0007 JAN 115.7 91.0 72.7 23.0 14.1 9.4 2039.0840 FEB 113.5 90.0 72.0 22.5 14.2 8.8 2039.1673 MAR 110.0 89.0 71.4 22.1 14.2 8.1 2039.2507 APR 105.8 87.8 71.1 21.8 14.4 7.5 2039.3340 MAY 103.2 86.8 70.8 21.4 14.5 7.4 2039.4173 JUN 101.6 86.0 70.5 20.8 14.4 7.7 2039.5007 JUL 100.1 85.1 70.6 20.0 14.3 8.1 2039.5840 AUG 98.1 84.1 70.4 20.0 14.1 8.5 2039.6673 SEP 96.5 83.0 69.9 20.2 13.9 8.5 2039.7507 OCT 94.6 82.0 69.6 19.8 13.8 8.5 2039.8340 NOV 93.5 81.3 69.5 19.4 13.6 8.4 2039.9173 DEC 93.1 80.7 69.5 18.9 13.6 8.4 2040.0007 JAN 92.3 80.0 69.3 18.2 13.6 8.3 2040.0840 FEB 91.2 79.3 69.1 17.3 13.5 8.0 2040.1673 MAR 90.3 78.5 68.8 17.3 13.4 7.6 2040.2507 APR 89.5 77.8 68.6 17.4 13.2 7.1 2040.3340 MAY 88.4 77.2 68.4 17.5 13.1 6.7 2040.4173 JUN 87.4 76.6 68.4 17.5 13.0 6.6 2040.5007 JUL 86.6 76.1 68.5 17.7 12.8 6.5 2040.5840 AUG 85.2 75.6 68.5 18.0 12.8 6.6 2040.6673 SEP 83.9 75.1 68.5 17.9 12.6 6.5 2040.7507 OCT 82.0 74.6 68.4 17.6 12.3 6.4 2040.8340 NOV 79.9 73.9 68.3 17.3 12.1 6.4 2040.9173 DEC 78.4 73.2 68.1 16.3 11.7 6.2 2041.0007 JAN 77.5 72.6 67.8 14.9 11.2 6.1 2041.0840 FEB 77.0 72.1 67.7 13.8 10.9 6.1 2041.1673 MAR 76.9 71.8 67.6 13.9 10.5 6.1 2041.2507 APR 76.6 71.5 67.5 13.6 10.2 6.2 2041.3340 MAY 76.5 71.1 67.3 13.2 9.8 6.2 2041.4173 JUN 76.1 70.8 67.1 12.9 9.5 6.0 2041.5007 JUL 75.1 70.5 67.1 12.6 9.3 5.9 2041.5840 AUG 74.2 70.2 67.0 11.9 9.1 5.7 2041.6673 SEP 74.0 70.0 67.0 11.4 8.9 5.2