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% 2020.5837 AUG 75.5 74.9 74.1 5.7 5.2 5.0 2020.6670 SEP 77.4 75.9 74.4 5.8 5.2 4.8 2020.7503 OCT 80.3 77.1 74.9 6.4 5.4 4.9 2020.8337 NOV 83.4 78.6 75.9 7.2 5.7 4.8 2020.9170 DEC 86.3 80.4 77.4 7.7 5.8 4.6 2021.0003 JAN 89.1 82.2 78.4 7.8 5.8 4.2 2021.0837 FEB 92.5 84.4 79.3 8.4 5.9 4.0 2021.1670 MAR 96.7 86.8 80.3 9.0 5.9 3.7 2021.2503 APR 101.2 89.4 81.1 9.8 6.0 3.2 2021.3337 MAY 106.6 92.3 82.5 10.9 6.2 3.1 2021.4170 JUN 113.0 95.3 84.6 11.9 6.5 3.2 2021.5003 JUL 119.1 98.4 85.3 12.1 6.7 3.2 2021.5837 AUG 124.7 101.6 86.0 12.1 6.9 3.2 2021.6670 SEP 129.6 104.8 87.5 11.5 6.9 3.2 2021.7503 OCT 134.5 107.9 89.3 10.9 6.7 3.3 2021.8337 NOV 140.5 111.1 91.1 10.3 6.6 3.5 2021.9170 DEC 147.5 114.5 92.6 9.9 6.7 3.5 2022.0003 JAN 154.9 118.3 93.8 9.9 6.8 3.8 2022.0837 FEB 162.7 122.0 95.3 9.9 7.1 4.7 2022.1670 MAR 171.3 125.7 96.6 10.2 7.5 5.3 2022.2503 APR 179.6 129.1 98.6 10.1 7.8 5.6 2022.3337 MAY 185.1 132.7 101.0 10.1 8.0 5.7 2022.4170 JUN 188.4 136.1 103.1 10.7 8.2 5.2 2022.5003 JUL 191.5 138.5 104.3 11.5 8.5 4.9 2022.5837 AUG 195.1 140.9 104.7 11.7 8.6 4.8 2022.6670 SEP 200.0 143.4 105.4 12.2 9.0 5.0 2022.7503 OCT 206.5 146.2 107.2 13.1 9.5 5.3 2022.8337 NOV 211.8 148.9 108.3 13.9 9.7 5.0 2022.9170 DEC 215.4 151.3 108.8 14.3 9.8 4.7 2023.0003 JAN 219.8 153.2 110.1 14.8 10.2 4.5 2023.0837 FEB 224.4 154.9 113.1 15.4 10.4 4.2 2023.1670 MAR 227.3 156.4 116.2 15.7 10.5 4.2 2023.2503 APR 229.5 157.8 119.5 16.2 10.5 4.4 2023.3337 MAY 231.6 158.9 123.2 17.2 10.6 4.4 2023.4170 JUN 233.1 159.6 123.2 17.4 10.6 4.5 2023.5003 JUL 234.9 159.9 121.6 16.8 10.7 4.9 2023.5837 AUG 237.7 159.9 120.2 16.5 10.8 5.3 2023.6670 SEP 238.7 160.0 119.0 16.0 10.8 5.5 2023.7503 OCT 237.9 160.2 120.7 15.4 10.5 5.5 2023.8337 NOV 237.0 160.0 121.8 15.3 10.6 5.7 2023.9170 DEC 237.5 159.6 122.6 15.1 10.6 5.9 2024.0003 JAN 237.0 158.8 122.6 14.4 10.4 5.6 2024.0837 FEB 233.8 157.5 120.7 13.6 10.3 5.9 2024.1670 MAR 230.1 156.6 118.9 12.8 9.8 6.0 2024.2503 APR 226.5 156.2 116.2 12.4 9.3 5.8 2024.3337 MAY 224.4 156.5 114.0 12.5 9.1 5.6 2024.4170 JUN 223.8 156.8 112.7 13.5 9.1 5.3 2024.5003 JUL 222.8 156.7 111.3 14.4 9.1 5.2 2024.5837 AUG 220.8 156.3 107.9 14.9 9.2 5.4 2024.6670 SEP 218.9 155.9 104.6 15.6 9.2 5.3 2024.7503 OCT 218.0 155.4 101.2 15.7 9.2 5.2 2024.8337 NOV 218.1 155.2 99.9 15.3 9.4 5.6 2024.9170 DEC 218.5 154.7 99.0 15.0 9.3 5.5 2025.0003 JAN 217.3 153.8 97.6 14.0 9.1 5.8 2025.0837 FEB 214.2 152.6 96.6 13.5 9.1 5.8 2025.1670 MAR 211.3 150.8 94.8 13.5 9.4 6.6 2025.2503 APR 208.6 149.2 94.0 14.4 9.7 6.8 2025.3337 MAY 205.8 147.8 91.9 14.6 9.9 7.0 2025.4170 JUN 202.1 146.5 91.0 15.0 10.3 6.9 2025.5003 JUL 199.2 144.7 90.7 15.5 10.5 7.2 2025.5837 AUG 195.6 142.7 90.7 14.7 10.3 7.0 2025.6670 SEP 191.2 140.3 91.0 15.0 10.4 6.8 2025.7503 OCT 187.8 138.1 91.6 15.6 10.7 6.9 2025.8337 NOV 184.6 136.2 91.8 15.6 10.8 6.8 2025.9170 DEC 181.7 134.6 92.3 15.4 10.8 6.7 2026.0003 JAN 178.8 132.6 93.1 15.5 10.9 6.6 2026.0837 FEB 175.1 130.5 92.9 15.6 11.2 6.5 2026.1670 MAR 171.4 129.1 92.6 14.9 11.6 7.1 2026.2503 APR 168.7 127.8 92.3 14.9 12.0 7.6 2026.3337 MAY 166.3 126.3 91.9 15.6 12.3 8.4 2026.4170 JUN 164.2 124.5 91.3 16.0 12.6 8.3 2026.5003 JUL 160.4 122.4 90.9 15.9 12.9 8.7 2026.5837 AUG 154.7 120.2 90.9 16.3 13.1 9.2 2026.6670 SEP 149.3 118.3 89.8 17.6 13.1 9.3 2026.7503 OCT 145.7 116.4 88.4 18.3 13.0 9.4 2026.8337 NOV 143.1 114.5 87.3 18.6 13.3 9.7 2026.9170 DEC 141.0 112.8 86.2 18.8 13.5 9.8 2027.0003 JAN 138.3 111.3 85.5 19.2 13.6 9.9 2027.0837 FEB 134.9 109.6 84.9 18.9 13.5 9.3 2027.1670 MAR 131.8 107.9 84.7 19.0 13.4 9.1 2027.2503 APR 128.9 106.2 83.6 19.5 13.3 9.1 2027.3337 MAY 126.0 104.4 82.2 19.7 13.1 8.6 2027.4170 JUN 124.7 102.4 80.7 20.0 12.7 7.6 2027.5003 JUL 124.4 100.8 79.7 20.5 12.3 6.7 2027.5837 AUG 123.7 99.5 78.3 21.1 12.1 6.7 2027.6670 SEP 123.3 98.2 77.4 21.6 12.0 6.8 2027.7503 OCT 122.2 97.0 76.8 22.0 12.1 6.8 2027.8337 NOV 120.2 96.1 76.6 21.7 11.8 6.8 2027.9170 DEC 118.5 94.9 76.0 21.1 11.6 6.9 2028.0003 JAN 117.3 93.6 75.1 20.2 11.4 6.4 2028.0837 FEB 116.2 92.3 74.3 19.5 11.4 6.0 2028.1670 MAR 114.5 91.1 73.4 19.4 11.7 5.8 2028.2503 APR 111.3 89.9 73.0 19.0 11.8 5.1 2028.3337 MAY 107.6 88.5 72.7 18.9 12.1 4.7 2028.4170 JUN 104.4 87.4 72.4 18.7 12.3 4.7 2028.5003 JUL 102.7 86.5 72.0 18.2 12.4 5.3 2028.5837 AUG 101.4 85.5 71.7 18.4 12.3 5.7 2028.6670 SEP 99.1 84.5 71.4 18.6 12.2 6.1 2028.7503 OCT 97.6 83.4 71.0 18.7 12.0 6.0 2028.8337 NOV 95.7 82.4 70.9 18.5 12.0 6.2 2028.9170 DEC 94.8 81.8 70.9 18.3 12.1 6.5 2029.0003 JAN 94.1 81.1 70.9 18.1 12.5 7.0 2029.0837 FEB 93.3 80.5 71.0 17.5 12.7 7.3 2029.1670 MAR 91.5 79.8 70.9 16.7 12.7 7.3 2029.2503 APR 90.1 79.1 70.8 16.7 12.4 7.1 2029.3337 MAY 89.2 78.5 70.6 16.7 12.1 6.9 2029.4170 JUN 88.1 77.8 70.5 16.7 11.9 6.5 2029.5003 JUL 87.2 77.2 70.3 16.8 11.8 6.0 2029.5837 AUG 86.4 76.6 70.1 17.3 12.0 6.0 2029.6670 SEP 85.0 76.0 70.0 17.7 12.0 6.4 2029.7503 OCT 83.6 75.5 69.7 17.6 11.9 6.6 2029.8337 NOV 81.6 74.9 69.6 17.3 11.7 6.6 2029.9170 DEC 79.7 74.2 69.3 17.0 11.4 6.4 2030.0003 JAN 78.7 73.5 68.9 15.9 10.9 6.4 2030.0837 FEB 77.9 72.9 68.5 14.3 10.3 6.3 2030.1670 MAR 77.4 72.4 68.3 13.0 9.8 6.0 2030.2503 APR 77.2 72.0 68.1 13.1 9.4 5.8 2030.3337 MAY 77.0 71.7 68.0 12.8 9.0 5.7 2030.4170 JUN 76.8 71.4 67.9 12.4 8.8 5.6 2030.5003 JUL 76.0 71.1 68.0 12.3 8.7 5.5 2030.5837 AUG 74.9 70.8 67.9 12.0 8.5 5.2 2030.6670 SEP 73.7 70.5 67.7 11.3 8.3 4.7 2030.7503 OCT 73.4 70.3 67.4 10.8 8.1 4.2 2030.8337 NOV 73.0 70.1 67.3 10.6 7.9 3.9 2030.9170 DEC 73.0 70.1 67.3 10.6 7.9 4.0 2031.0003 JAN 73.1 70.2 67.3 10.9 8.1 3.8 2031.0837 FEB 73.8 70.5 67.3 11.2 8.3 3.9 2031.1670 MAR 74.7 70.9 67.4 11.4 8.4 3.8 2031.2503 APR 75.4 71.2 67.5 11.6 8.6 3.6 2031.3337 MAY 76.6 71.6 67.6 11.8 8.7 3.4 2031.4170 JUN 78.3 72.1 67.7 11.9 8.8 3.4 2031.5003 JUL 79.7 72.8 67.8 12.1 9.0 3.4 2031.5837 AUG 81.0 73.5 67.9 12.4 9.2 3.3 2031.6670 SEP 83.3 74.3 68.0 12.8 9.5 3.4 2031.7503 OCT 86.2 75.3 68.1 13.2 10.0 3.7 2031.8337 NOV 90.9 76.4 68.4 13.8 10.4 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