| E | O (JD) | O (dat) | Period |
| -46 | 2415680 | 1901-10-22 | 561.52 |
| -41 | 2418680 | 1910-01-08 | 556.11 |
| -39 | 2419795 | 1913-01-27 | 553.94 |
| -37 | 2420850 | 1915-12-18 | 562.21 |
| -35 | 2421980 | 1919-01-21 | 557.69 |
| -33 | 2423030 | 1921-12-06 | 553.41 |
| -32 | 2423630 | 1923-07-29 | 562.14 |
| -31 | 2424140 | 1924-12-20 | 567.68 |
| -30 | 2424720 | 1926-07-23 | 577.12 |
| -28 | 2425930 | 1929-11-14 | 586.25 |
| -27 | 2426520 | 1931-06-27 | 594.56 |
| -26 | 2427096 | 1933-01-23 | 605.5 |
| -25 | 2427725 | 1934-10-14 | 610.67 |
| -24 | 2428315 | 1936-05-26 | 615.33 |
| -23 | 2428968 | 1938-03-10 | 621.5 |
| -22 | 2429580 | 1939-11-12 | 626.81 |
| -21 | 2430230 | 1941-08-23 | 627.65 |
| -19 | 2431450 | 1944-12-25 | 628.43 |
| -18 | 2432110 | 1946-10-16 | 625.48 |
| -17 | 2432740 | 1948-07-07 | 622.85 |
| -15 | 2433970 | 1951-11-19 | 623.67 |
| -11 | 2436510 | 1958-11-02 | 624.84 |
| -5 | 2440177 | 1968-11-16 | 624.16 |
| -4 | 2440810 | 1970-08-11 | 626.29 |
| -3 | 2441451 | 1972-05-13 | 631.5 |
| -2 | 2442104 | 1974-02-25 | 641.71 |
| -1 | 2442719 | 1975-11-02 | 654.13 |
| 0 | 2443406 | 1977-09-19 | 656.56 |
| 2 | 2444756 | 1981-05-31 | 658.81 |
| 3 | 2445407 | 1983-03-13 | 659.94 |
| 4 | 2446046 | 1984-12-11 | 657.19 |
| 5 | 2446720 | 1986-10-16 | 649.27 |
| 6 | 2447376 | 1988-08-02 | 644.14 |
| 7 | 2448006 | 1990-04-24 | 645.14 |
| 8 | 2448634 | 1992-01-12 | 642.57 |
| 9 | 2449267 | 1993-10-06 | 640.29 |
| 10 | 2449914 | 1995-07-15 | 642.71 |
| 11 | 2450571 | 1997-05-02 | 644.57 |
| 12 | 2451191 | 1999-01-12 | 646.57 |
| 13 | 2451869 | 2000-11-20 | 647.86 |
| 14 | 2452511 | 2002-08-24 | 647.5 |
| 15 | 2453153 | 2004-05-27 | 649.57 |
| 16 | 2453800 | 2006-03-05 | 648.36 |
| 17 | 2454451 | 2007-12-16 | 646.07 |
| 18 | 2455099 | 2009-09-24 | 644.14 |
| 19 | 2455757 | 2011-07-14 | 637.93 |
| 20 | 2456380 | 2013-03-28 | 631 |
| 21 | 2457045 | 2015-01-22 | 623.07 |
| 22 | 2457637 | 2016-09-05 | 619.94 |
| 23 | 2458247 | 2018-05-08 | 620.54 |
| 24 | 2458838 | 2019-12-20 | 608.92 |
| 25 | 2459435 | 2021-08-08 | 597.7 |
| 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. |