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% 2021.6670 SEP 89.9 87.9 86.0 9.0 7.9 7.3 2021.7503 OCT 94.2 90.1 86.8 10.3 8.1 7.1 2021.8337 NOV 97.9 92.4 87.7 10.8 8.1 6.8 2021.9170 DEC 103.4 94.8 88.4 11.2 8.3 6.5 2022.0003 JAN 108.9 97.2 88.4 11.5 8.5 6.6 2022.0837 FEB 114.5 99.7 87.7 12.2 8.9 6.5 2022.1670 MAR 120.1 102.1 87.7 13.2 9.4 6.7 2022.2503 APR 127.0 104.8 87.1 14.0 9.9 6.9 2022.3337 MAY 133.9 107.5 87.2 14.7 10.3 7.2 2022.4170 JUN 140.2 110.3 87.3 15.1 10.6 7.6 2022.5003 JUL 146.5 112.8 86.9 14.8 10.7 7.7 2022.5837 AUG 151.4 114.8 88.1 15.0 10.7 7.4 2022.6670 SEP 155.7 116.6 87.4 14.8 10.9 7.2 2022.7503 OCT 161.2 118.8 85.5 14.2 11.1 7.1 2022.8337 NOV 169.6 121.1 83.4 14.7 11.2 6.6 2022.9170 DEC 177.4 123.5 80.8 15.0 11.2 6.2 2023.0003 JAN 182.8 125.5 78.3 15.0 11.4 5.8 2023.0837 FEB 186.5 127.3 77.2 15.4 11.6 5.5 2023.1670 MAR 190.2 129.0 77.1 15.4 11.5 5.3 2023.2503 APR 194.3 130.7 78.6 15.3 11.4 5.2 2023.3337 MAY 197.5 132.1 79.5 16.1 11.3 4.9 2023.4170 JUN 198.6 133.2 79.4 16.2 11.2 4.7 2023.5003 JUL 198.7 134.2 79.1 15.9 11.3 5.2 2023.5837 AUG 197.8 134.7 77.7 15.8 11.5 5.8 2023.6670 SEP 196.0 135.2 77.0 15.5 11.5 6.3 2023.7503 OCT 193.5 135.8 79.1 15.1 11.4 6.5 2023.8337 NOV 192.4 136.4 81.3 15.0 11.4 6.6 2023.9170 DEC 191.7 136.7 82.8 14.8 11.4 6.7 2024.0003 JAN 190.0 136.3 82.0 14.9 11.4 6.8 2024.0837 FEB 187.6 135.3 80.6 15.4 11.6 7.5 2024.1670 MAR 185.0 134.9 79.9 15.5 11.4 7.9 2024.2503 APR 182.5 135.0 78.9 15.9 11.1 7.2 2024.3337 MAY 181.1 135.5 77.6 16.7 11.0 7.5 2024.4170 JUN 181.1 136.1 76.1 18.1 11.2 7.9 2024.5003 JUL 180.9 136.3 74.7 19.3 11.4 8.0 2024.5837 AUG 180.3 136.5 72.3 20.0 11.6 8.0 2024.6670 SEP 179.4 136.5 70.4 21.0 11.8 7.7 2024.7503 OCT 179.4 136.3 68.3 21.4 11.9 7.2 2024.8337 NOV 180.8 136.3 67.4 20.7 11.9 7.2 2024.9170 DEC 181.9 136.1 67.0 20.7 12.0 7.1 2025.0003 JAN 181.2 135.5 65.9 19.9 12.0 6.8 2025.0837 FEB 178.6 134.5 65.4 18.0 11.9 6.4 2025.1670 MAR 176.8 133.3 65.1 16.4 12.1 6.3 2025.2503 APR 176.0 132.0 65.3 16.2 12.5 6.7 2025.3337 MAY 175.5 130.9 65.1 16.5 12.7 7.1 2025.4170 JUN 175.2 130.0 66.0 17.3 12.8 7.6 2025.5003 JUL 176.3 129.0 67.3 18.1 12.9 7.8 2025.5837 AUG 176.4 127.6 69.0 18.9 12.8 7.5 2025.6670 SEP 175.2 126.2 71.2 19.3 12.8 7.5 2025.7503 OCT 173.9 125.1 73.6 19.7 13.0 7.9 2025.8337 NOV 173.7 124.3 75.3 19.6 13.0 7.7 2025.9170 DEC 172.7 123.6 77.1 19.1 13.2 7.6 2026.0003 JAN 170.1 122.2 78.9 18.1 13.2 7.5 2026.0837 FEB 167.3 120.7 79.7 16.8 13.2 7.4 2026.1670 MAR 164.5 119.7 80.3 16.9 13.4 7.7 2026.2503 APR 161.8 118.8 80.2 17.2 13.7 8.2 2026.3337 MAY 160.1 117.7 79.3 17.6 13.9 9.0 2026.4170 JUN 158.8 116.3 79.0 17.7 14.0 9.6 2026.5003 JUL 155.5 114.8 79.2 18.1 14.2 9.8 2026.5837 AUG 149.9 113.4 79.4 19.3 14.3 10.1 2026.6670 SEP 144.2 111.9 78.8 20.4 14.4 10.4 2026.7503 OCT 140.9 110.1 78.0 21.0 14.4 10.9 2026.8337 NOV 139.2 108.4 77.5 21.1 14.6 11.5 2026.9170 DEC 137.7 106.8 77.5 20.7 14.6 10.9 2027.0003 JAN 135.2 105.3 77.6 20.1 14.7 10.3 2027.0837 FEB 132.2 103.9 77.7 19.3 14.6 9.7 2027.1670 MAR 129.6 102.6 78.2 18.3 14.4 9.3 2027.2503 APR 127.5 101.5 78.3 18.3 14.0 8.8 2027.3337 MAY 124.9 100.2 77.4 18.3 13.6 8.2 2027.4170 JUN 120.7 98.8 76.3 18.4 13.3 6.9 2027.5003 JUL 119.9 97.5 75.4 18.5 12.8 5.7 2027.5837 AUG 119.4 96.3 74.1 18.4 12.3 5.2 2027.6670 SEP 119.2 95.1 73.3 18.5 12.0 4.9 2027.7503 OCT 118.3 94.1 72.9 18.6 11.9 4.7 2027.8337 NOV 117.2 93.1 72.6 18.1 11.7 4.5 2027.9170 DEC 116.8 92.1 72.2 17.5 11.5 4.7 2028.0003 JAN 115.7 91.1 71.7 16.9 11.4 5.0 2028.0837 FEB 114.5 90.1 71.4 16.4 11.4 5.5 2028.1670 MAR 113.1 89.5 71.5 16.3 11.6 5.8 2028.2503 APR 109.9 88.7 71.6 16.1 11.8 6.0 2028.3337 MAY 105.9 87.6 71.2 17.1 12.1 5.6 2028.4170 JUN 103.1 86.6 70.9 17.4 12.3 5.6 2028.5003 JUL 101.4 85.9 70.6 17.7 12.4 6.1 2028.5837 AUG 100.2 85.1 70.5 18.1 12.4 6.6 2028.6670 SEP 97.8 84.3 70.1 18.4 12.4 7.0 2028.7503 OCT 96.3 83.3 69.6 18.6 12.2 7.0 2028.8337 NOV 94.3 82.2 69.5 18.4 12.2 7.1 2028.9170 DEC 93.3 81.4 69.4 18.1 12.3 7.2 2029.0003 JAN 93.0 80.8 69.4 17.8 12.4 7.4 2029.0837 FEB 92.3 80.0 69.3 17.2 12.5 7.5 2029.1670 MAR 91.2 79.2 69.2 16.9 12.5 7.4 2029.2503 APR 90.3 78.3 68.8 17.2 12.3 7.3 2029.3337 MAY 89.3 77.6 68.6 17.3 12.1 7.1 2029.4170 JUN 88.3 76.9 68.5 17.4 12.0 7.0 2029.5003 JUL 87.3 76.3 68.5 17.4 11.9 6.5 2029.5837 AUG 86.5 75.9 68.5 17.5 12.1 6.4 2029.6670 SEP 85.2 75.4 68.5 17.7 12.1 6.7 2029.7503 OCT 83.7 75.0 68.5 17.6 12.0 6.5 2029.8337 NOV 81.7 74.4 68.5 17.4 11.9 6.5 2029.9170 DEC 79.5 73.7 68.5 17.1 11.6 6.3 2030.0003 JAN 78.1 73.0 68.3 16.0 11.2 6.3 2030.0837 FEB 77.4 72.4 68.0 14.5 10.7 6.2 2030.1670 MAR 77.1 72.0 67.8 13.3 10.3 6.3 2030.2503 APR 76.9 71.7 67.7 13.4 10.0 6.4 2030.3337 MAY 76.7 71.4 67.6 13.0 9.6 6.4 2030.4170 JUN 76.5 71.0 67.4 12.6 9.3 6.2 2030.5003 JUL 75.8 70.6 67.4 12.4 9.0 6.1 2030.5837 AUG 74.7 70.3 67.4 12.1 8.8 5.8 2030.6670 SEP 73.6 70.0 67.3 11.3 8.5 5.2 2030.7503 OCT 73.3 69.8 67.0 11.0 8.3 4.7 2030.8337 NOV 72.9 69.6 66.9 10.6 8.1 4.4 2030.9170 DEC 72.9 69.6 66.9 10.6 8.1 4.4 2031.0003 JAN 73.1 69.7 66.9 10.9 8.2 4.2 2031.0837 FEB 73.8 70.1 67.0 11.2 8.4 4.2 2031.1670 MAR 74.7 70.5 67.1 11.4 8.6 4.1 2031.2503 APR 75.4 70.9 67.2 11.6 8.7 3.9 2031.3337 MAY 76.5 71.3 67.4 11.8 8.8 3.7 2031.4170 JUN 78.2 71.9 67.5 11.9 8.9 3.6 2031.5003 JUL 79.6 72.6 67.7 12.1 9.0 3.5 2031.5837 AUG 81.0 73.4 67.8 12.4 9.3 3.4 2031.6670 SEP 83.3 74.2 68.0 12.8 9.5 3.5 2031.7503 OCT 86.2 75.2 68.1 13.2 10.0 3.8 2031.8337 NOV 90.8 76.4 68.4 13.8 10.3 4.2 2031.9170 DEC 95.1 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 208.8 135.1 75.8 20.5 14.7 8.1 2033.8337 NOV 213.0 137.6 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 198.5 133.5 96.3 22.7 15.9 8.1 2036.7503 OCT 194.7 131.8 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 88.5 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 160.7 116.7 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 118.5 97.5 75.6 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 70.6 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 68.0 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