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% 2020.2503 APR 71.3 70.4 69.8 5.4 5.2 5.0 2020.3337 MAY 72.1 70.8 69.6 5.9 5.3 4.8 2020.4170 JUN 73.6 71.3 69.9 6.4 5.3 4.5 2020.5003 JUL 74.9 71.9 69.9 6.9 5.3 4.2 2020.5837 AUG 76.1 72.6 70.1 7.4 5.3 4.0 2020.6670 SEP 78.0 73.4 69.9 7.6 5.3 3.9 2020.7503 OCT 80.4 74.2 69.6 7.8 5.5 3.9 2020.8337 NOV 84.3 75.3 69.9 8.0 5.7 4.0 2020.9170 DEC 87.9 76.5 70.5 8.1 5.8 4.3 2021.0003 JAN 90.7 77.9 70.7 8.1 5.7 4.0 2021.0837 FEB 94.9 79.4 70.6 8.0 5.6 3.7 2021.1670 MAR 99.7 81.2 70.8 8.1 5.6 3.5 2021.2503 APR 104.4 83.0 70.6 8.6 5.6 3.0 2021.3337 MAY 110.3 85.1 70.3 9.6 5.7 2.7 2021.4170 JUN 117.2 87.2 70.4 10.4 5.9 2.7 2021.5003 JUL 122.5 89.5 71.0 10.6 6.0 2.6 2021.5837 AUG 126.3 92.1 72.1 10.5 6.1 2.6 2021.6670 SEP 129.7 94.6 72.7 10.0 6.1 2.6 2021.7503 OCT 133.2 97.2 73.0 9.4 6.1 2.8 2021.8337 NOV 138.8 99.8 74.0 8.8 6.0 3.0 2021.9170 DEC 145.6 102.6 75.4 8.3 6.1 3.1 2022.0003 JAN 152.0 105.5 75.9 8.7 6.3 3.4 2022.0837 FEB 158.3 108.3 76.6 9.8 6.7 4.4 2022.1670 MAR 165.7 111.2 76.8 10.2 7.2 5.0 2022.2503 APR 172.5 114.1 78.7 10.2 7.6 5.2 2022.3337 MAY 176.8 117.2 81.0 10.3 7.8 5.4 2022.4170 JUN 179.3 120.1 82.7 10.9 8.1 4.9 2022.5003 JUL 182.2 122.5 83.7 11.6 8.2 4.5 2022.5837 AUG 185.4 124.6 83.7 11.7 8.3 4.3 2022.6670 SEP 190.4 126.7 83.5 12.3 8.7 4.5 2022.7503 OCT 196.5 129.1 84.3 13.2 9.2 4.8 2022.8337 NOV 201.2 131.5 83.8 13.9 9.3 4.4 2022.9170 DEC 204.3 133.7 84.2 14.1 9.3 4.0 2023.0003 JAN 208.3 135.6 85.0 14.1 9.7 3.7 2023.0837 FEB 212.5 137.4 88.3 13.8 10.0 3.6 2023.1670 MAR 214.7 139.0 92.2 13.7 10.0 3.5 2023.2503 APR 216.6 140.5 93.5 14.1 10.0 3.5 2023.3337 MAY 218.9 141.6 94.6 14.9 9.9 3.2 2023.4170 JUN 221.1 142.3 93.8 15.1 9.8 3.2 2023.5003 JUL 224.0 143.0 92.6 14.7 10.0 3.7 2023.5837 AUG 227.0 143.4 92.4 14.6 10.2 4.2 2023.6670 SEP 228.0 143.6 93.0 14.1 10.2 4.6 2023.7503 OCT 226.0 144.0 94.0 13.5 10.0 4.6 2023.8337 NOV 224.6 144.2 95.7 13.5 10.0 4.8 2023.9170 DEC 225.5 144.3 97.6 13.4 10.1 4.9 2024.0003 JAN 225.4 143.8 98.7 12.9 9.8 4.6 2024.0837 FEB 222.6 142.7 99.5 12.6 9.7 4.9 2024.1670 MAR 218.7 142.0 100.5 12.2 9.2 5.0 2024.2503 APR 215.2 141.9 101.7 12.1 8.7 4.9 2024.3337 MAY 213.9 142.2 103.0 12.3 8.6 4.7 2024.4170 JUN 214.1 142.6 104.3 13.3 8.6 4.4 2024.5003 JUL 213.7 142.6 105.7 14.2 8.6 4.3 2024.5837 AUG 212.1 142.5 105.9 14.7 8.7 4.6 2024.6670 SEP 210.0 142.2 103.7 15.4 8.7 4.6 2024.7503 OCT 208.5 141.8 100.7 15.5 8.6 4.4 2024.8337 NOV 209.2 141.7 99.2 15.0 8.8 4.7 2024.9170 DEC 209.7 141.5 98.0 15.0 8.9 4.7 2025.0003 JAN 208.6 140.7 96.9 14.1 8.8 5.6 2025.0837 FEB 205.6 139.6 95.2 12.7 8.8 5.7 2025.1670 MAR 201.6 138.2 93.3 12.8 9.1 5.8 2025.2503 APR 198.7 136.6 92.7 13.2 9.5 5.9 2025.3337 MAY 195.8 135.0 91.9 13.9 9.8 6.2 2025.4170 JUN 192.2 133.8 90.9 15.0 10.2 6.8 2025.5003 JUL 189.3 132.4 90.5 16.0 10.5 7.3 2025.5837 AUG 186.4 130.8 90.3 16.8 10.4 7.1 2025.6670 SEP 182.9 129.0 90.5 17.2 10.4 6.9 2025.7503 OCT 180.0 127.6 91.0 17.7 10.7 7.0 2025.8337 NOV 176.6 126.6 91.0 17.6 10.7 6.9 2025.9170 DEC 174.1 125.6 91.4 17.0 10.7 6.7 2026.0003 JAN 170.8 124.0 92.0 16.0 10.7 6.5 2026.0837 FEB 167.2 122.3 91.8 14.7 10.7 6.4 2026.1670 MAR 164.6 121.2 91.5 14.1 11.2 6.9 2026.2503 APR 162.2 120.2 90.9 14.2 11.6 7.4 2026.3337 MAY 160.1 118.9 89.4 14.9 11.9 8.2 2026.4170 JUN 156.7 117.4 88.6 15.0 12.0 7.8 2026.5003 JUL 152.0 115.7 87.9 14.6 12.2 8.0 2026.5837 AUG 147.2 114.2 87.2 15.6 12.3 8.5 2026.6670 SEP 142.9 112.6 86.2 16.9 12.4 8.8 2026.7503 OCT 138.7 110.7 84.9 17.8 12.5 9.8 2026.8337 NOV 134.4 108.8 83.8 18.2 12.9 9.2 2026.9170 DEC 130.7 107.0 83.5 18.1 13.1 9.0 2027.0003 JAN 127.7 105.5 83.4 18.5 13.3 8.7 2027.0837 FEB 124.8 103.9 82.9 18.5 13.4 8.3 2027.1670 MAR 123.4 102.4 82.6 18.6 13.3 8.2 2027.2503 APR 123.3 101.1 81.9 19.1 13.2 8.2 2027.3337 MAY 123.4 99.7 81.5 19.4 13.1 7.9 2027.4170 JUN 123.3 98.2 80.5 19.9 12.8 7.0 2027.5003 JUL 123.1 96.8 79.6 20.4 12.4 6.0 2027.5837 AUG 122.5 95.7 78.3 20.7 12.0 5.8 2027.6670 SEP 122.2 94.6 77.4 21.0 11.8 5.6 2027.7503 OCT 121.1 93.5 76.9 21.3 11.7 5.5 2027.8337 NOV 119.1 92.7 76.6 20.9 11.4 5.4 2027.9170 DEC 116.9 91.8 76.1 20.2 11.1 5.3 2028.0003 JAN 115.2 90.7 75.2 19.2 10.9 5.4 2028.0837 FEB 114.6 89.7 74.4 18.5 10.9 5.7 2028.1670 MAR 113.6 88.9 73.5 18.2 11.1 6.0 2028.2503 APR 111.2 88.0 73.1 17.9 11.2 5.5 2028.3337 MAY 107.7 86.9 72.9 17.7 11.4 5.0 2028.4170 JUN 105.0 85.9 72.6 17.5 11.6 5.0 2028.5003 JUL 103.0 85.1 72.3 17.7 11.8 5.5 2028.5837 AUG 101.5 84.3 72.2 18.1 11.8 6.1 2028.6670 SEP 100.0 83.5 71.9 18.4 11.7 6.4 2028.7503 OCT 98.1 82.4 71.6 18.5 11.5 6.4 2028.8337 NOV 96.2 81.4 71.3 18.3 11.6 6.6 2028.9170 DEC 95.1 80.7 71.1 18.1 11.7 6.8 2029.0003 JAN 94.6 80.1 71.0 17.8 12.1 7.1 2029.0837 FEB 93.3 79.4 71.0 17.2 12.3 7.3 2029.1670 MAR 91.1 78.6 70.8 16.4 12.2 7.2 2029.2503 APR 89.2 77.9 70.3 16.4 11.9 7.0 2029.3337 MAY 87.7 77.2 70.0 16.4 11.6 6.9 2029.4170 JUN 86.3 76.6 69.9 16.4 11.3 6.5 2029.5003 JUL 85.4 76.1 69.9 16.4 11.2 5.9 2029.5837 AUG 84.8 75.6 69.8 16.8 11.4 5.8 2029.6670 SEP 83.5 75.2 69.7 17.2 11.5 6.2 2029.7503 OCT 81.9 74.7 69.2 17.2 11.4 6.6 2029.8337 NOV 80.1 74.2 69.1 17.0 11.3 6.6 2029.9170 DEC 79.2 73.5 68.8 16.7 11.1 6.4 2030.0003 JAN 78.0 72.9 68.5 15.6 10.6 6.3 2030.0837 FEB 77.3 72.3 68.3 14.1 10.0 6.3 2030.1670 MAR 76.8 71.9 68.1 12.9 9.6 6.2 2030.2503 APR 76.6 71.6 68.1 13.0 9.2 6.1 2030.3337 MAY 76.4 71.2 67.9 12.7 8.9 5.9 2030.4170 JUN 76.1 70.9 67.8 12.3 8.6 5.8 2030.5003 JUL 75.2 70.6 67.7 12.1 8.5 5.7 2030.5837 AUG 74.2 70.3 67.4 11.8 8.3 5.3 2030.6670 SEP 73.1 70.0 67.2 11.1 7.9 4.7 2030.7503 OCT 72.5 69.8 66.9 10.5 7.7 4.2 2030.8337 NOV 72.3 69.6 67.0 10.3 7.5 3.9 2030.9170 DEC 72.4 69.6 67.0 10.4 7.6 3.9 2031.0003 JAN 72.6 69.8 67.0 10.7 7.7 3.8 2031.0837 FEB 73.3 70.1 67.1 11.0 8.0 3.9 2031.1670 MAR 74.3 70.5 67.2 11.2 8.2 3.8 2031.2503 APR 75.1 70.9 67.3 11.5 8.3 3.6 2031.3337 MAY 76.3 71.3 67.4 11.7 8.5 3.4 2031.4170 JUN 78.0 71.9 67.6 11.8 8.7 3.4 2031.5003 JUL 79.5 72.6 67.7 12.0 8.8 3.4 2031.5837 AUG 80.9 73.4 67.8 12.4 9.1 3.3 2031.6670 SEP 83.2 74.2 68.0 12.8 9.5 3.4 2031.7503 OCT 86.2 75.2 68.1 13.2 9.9 3.7 2031.8337 NOV 90.9 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