| E | O (JD) | O (dat) | Period |
| -46 | 2415680 | 1901-10-22 | 564.4 |
| -41 | 2418680 | 1910-01-08 | 562.8 |
| -39 | 2419795 | 1913-01-27 | 560.3 |
| -37 | 2420850 | 1915-12-18 | 559.35 |
| -35 | 2421980 | 1919-01-21 | 561.04 |
| -33 | 2423030 | 1921-12-06 | 562.7 |
| -32 | 2423630 | 1923-07-29 | 559.55 |
| -31 | 2424140 | 1924-12-20 | 566.41 |
| -30 | 2424720 | 1926-07-23 | 575.18 |
| -28 | 2425930 | 1929-11-14 | 584.54 |
| -27 | 2426520 | 1931-06-27 | 595.67 |
| -26 | 2427096 | 1933-01-23 | 602.39 |
| -25 | 2427725 | 1934-10-14 | 610.35 |
| -24 | 2428315 | 1936-05-26 | 616.19 |
| -23 | 2428968 | 1938-03-10 | 621.29 |
| -22 | 2429600 | 1939-12-02 | 624.2 |
| -21 | 2430230 | 1941-08-23 | 627.41 |
| -19 | 2431450 | 1944-12-25 | 624.63 |
| -18 | 2432110 | 1946-10-16 | 623.91 |
| -17 | 2432740 | 1948-07-07 | 623.29 |
| -15 | 2433970 | 1951-11-19 | 623.62 |
| -11 | 2436510 | 1958-11-02 | 623.75 |
| -5 | 2440177 | 1968-11-16 | 624.92 |
| -4 | 2440810 | 1970-08-11 | 627.05 |
| -3 | 2441451 | 1972-05-13 | 630.2 |
| -2 | 2442104 | 1974-02-25 | 634.72 |
| -1 | 2442719 | 1975-11-02 | 642.41 |
| 0 | 2443406 | 1977-09-19 | 656.81 |
| 2 | 2444756 | 1981-05-31 | 657.72 |
| 3 | 2445407 | 1983-03-13 | 656.89 |
| 4 | 2446046 | 1984-12-11 | 654.81 |
| 5 | 2446720 | 1986-10-16 | 652.54 |
| 6 | 2447376 | 1988-08-02 | 648.22 |
| 7 | 2448006 | 1990-04-24 | 643.52 |
| 8 | 2448634 | 1992-01-12 | 643.45 |
| 9 | 2449267 | 1993-10-06 | 643.42 |
| 10 | 2449914 | 1995-07-15 | 642.84 |
| 11 | 2450571 | 1997-05-02 | 643.82 |
| 12 | 2451191 | 1999-01-12 | 645.81 |
| 13 | 2451869 | 2000-11-20 | 647.3 |
| 14 | 2452511 | 2002-08-24 | 648.47 |
| 15 | 2453153 | 2004-05-27 | 647.74 |
| 16 | 2453800 | 2006-03-05 | 647.85 |
| 17 | 2454451 | 2007-12-16 | 645.89 |
| 18 | 2455099 | 2009-09-24 | 641.24 |
| 19 | 2455757 | 2011-07-14 | 636.28 |
| 20 | 2456380 | 2013-03-28 | 630.13 |
| 21 | 2457045 | 2015-01-22 | 627.08 |
| 22 | 2457637 | 2016-09-05 | 623.17 |
| 23 | 2458247 | 2018-05-08 | 618.45 |
| 24 | 2458838 | 2019-12-20 | 612.57 |
| 25 | 2459435 | 2021-08-08 | 607.54 |
| 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. |