| E | O (JD) | O (dat) | Period |
| -68 | 2404312 | 1870-09-06 | 569.59 |
| -67 | 2404846 | 1872-02-22 | 568.9 |
| -66 | 2405447 | 1873-10-15 | 569.45 |
| -64 | 2406614 | 1876-12-25 | 569.45 |
| -63 | 2407164 | 1878-06-28 | 569.28 |
| -55 | 2411703 | 1890-12-01 | 569.19 |
| -54 | 2412266 | 1892-06-16 | 568.98 |
| -53 | 2412861 | 1894-02-01 | 567.85 |
| -52 | 2413419 | 1895-08-13 | 566.91 |
| -51 | 2413980 | 1897-02-24 | 566.81 |
| -50 | 2414550 | 1898-09-17 | 564.14 |
| -49 | 2415106 | 1900-03-27 | 562.8 |
| -48 | 2415679 | 1901-10-21 | 560.58 |
| -47 | 2416233 | 1903-04-28 | 559.55 |
| -46 | 2416793 | 1904-11-08 | 559.33 |
| -45 | 2417340 | 1906-05-09 | 559.65 |
| -44 | 2417913 | 1907-12-03 | 561.07 |
| -43 | 2418460 | 1909-06-02 | 561.68 |
| -42 | 2419011 | 1910-12-05 | 562.37 |
| -41 | 2419589 | 1912-07-05 | 562.54 |
| -39 | 2420719 | 1915-08-09 | 562.16 |
| -37 | 2421856 | 1918-09-19 | 561.05 |
| -36 | 2422413 | 1920-03-29 | 559.41 |
| -35 | 2422969 | 1921-10-06 | 556.31 |
| -34 | 2423523 | 1923-04-13 | 552.09 |
| -33 | 2424067 | 1924-10-08 | 547.66 |
| -32 | 2424618 | 1926-04-12 | 544.21 |
| -31 | 2425145 | 1927-09-21 | 542.7 |
| -30 | 2425675 | 1929-03-04 | 542.05 |
| -29 | 2426221 | 1930-09-01 | 541.62 |
| -28 | 2426768 | 1932-03-01 | 541.45 |
| -27 | 2427317 | 1933-09-01 | 541.56 |
| -26 | 2427854 | 1935-02-20 | 542.95 |
| -25 | 2428404 | 1936-08-23 | 543.95 |
| -24 | 2428940 | 1938-02-10 | 544.08 |
| -23 | 2429475 | 1939-07-30 | 544.96 |
| -22 | 2430019 | 1941-01-24 | 545.98 |
| -21 | 2430576 | 1942-08-04 | 547.65 |
| -20 | 2431127 | 1944-02-06 | 548.55 |
| -19 | 2431668 | 1945-07-31 | 550.21 |
| -18 | 2432228 | 1947-02-11 | 551.09 |
| -17 | 2432776 | 1948-08-12 | 551.32 |
| -16 | 2433333 | 1950-02-20 | 551.36 |
| -15 | 2433875 | 1951-08-16 | 552.15 |
| -14 | 2434436 | 1953-02-27 | 552.55 |
| -13 | 2434982 | 1954-08-27 | 551.86 |
| -12 | 2435534 | 1956-03-01 | 551.65 |
| -11 | 2436089 | 1957-09-07 | 551.26 |
| -10 | 2436651 | 1959-03-23 | 550.14 |
| -9 | 2437196 | 1960-09-18 | 547.89 |
| -8 | 2437737 | 1962-03-13 | 546.06 |
| -7 | 2438289 | 1963-09-16 | 544.34 |
| -6 | 2438840 | 1965-03-20 | 542.79 |
| -5 | 2439368 | 1966-08-30 | 541.22 |
| -4 | 2439900 | 1968-02-13 | 541.02 |
| -3 | 2440441 | 1969-08-07 | 541.14 |
| -2 | 2440989 | 1971-02-06 | 541.48 |
| -1 | 2441532 | 1972-08-02 | 541.85 |
| 0 | 2442065 | 1974-01-17 | 541.92 |
| 1 | 2442616 | 1975-07-22 | 541.9 |
| 2 | 2443162 | 1977-01-18 | 540.95 |
| 3 | 2443711 | 1978-07-21 | 539.13 |
| 4 | 2444244 | 1980-01-05 | 537.35 |
| 5 | 2444767 | 1981-06-11 | 534.83 |
| 6 | 2445317 | 1982-12-13 | 531.43 |
| 7 | 2445848 | 1984-05-27 | 528.82 |
| 8 | 2446369 | 1985-10-30 | 526.43 |
| 9 | 2446898 | 1987-04-12 | 524.81 |
| 10 | 2447412 | 1988-09-07 | 522.94 |
| 11 | 2447929 | 1990-02-06 | 521.5 |
| 12 | 2448458 | 1991-07-20 | 520.68 |
| 13 | 2448976 | 1992-12-19 | 519.59 |
| 14 | 2449497 | 1994-05-24 | 518.06 |
| 15 | 2450009 | 1995-10-18 | 516.57 |
| 16 | 2450544 | 1997-04-05 | 514.65 |
| 17 | 2451053 | 1998-08-27 | 512.16 |
| 18 | 2451557 | 2000-01-13 | 509.14 |
| 19 | 2452064 | 2001-06-03 | 506.71 |
| 20 | 2452569 | 2002-10-21 | 504.83 |
| 21 | 2453077 | 2004-03-12 | 503.41 |
| 22 | 2453577 | 2005-07-25 | 502.66 |
| 23 | 2454060 | 2006-11-20 | 502.36 |
| 24 | 2454572 | 2008-04-15 | 502.31 |
| 25 | 2455078 | 2009-09-03 | 502.23 |
| 26 | 2455590 | 2011-01-28 | 503 |
| 27 | 2456079 | 2012-05-31 | 503.76 |
| 28 | 2456585 | 2013-10-19 | 503.9 |
| 29 | 2457092 | 2015-03-10 | 502.92 |
| 30 | 2457590 | 2016-07-20 | 502.65 |
| 31 | 2458108 | 2017-12-20 | 502.45 |
| 32 | 2458606 | 2019-05-02 | 503.07 |
| 33 | 2459098 | 2020-09-05 | 502.39 |
| 34 | 2459598 | 2022-01-18 | 501.49 |
| E | Cycle number from the GCVS4 epoch. |
| O (JD) | Julian date at observed time for maximum. |
| O (Dat) | Same as above, expressed as date. |
| Period | Calculated mean period at cycle number E. |