| E | O (JD) | O (dat) | Period |
| -81 | 2414898 | 1899-08-31 | 324.24 |
| -72 | 2417820 | 1907-09-01 | 324.4 |
| -48 | 2425551 | 1928-10-31 | 325.11 |
| -33 | 2430430 | 1942-03-11 | 324.95 |
| -24 | 2433361 | 1950-03-20 | 324.54 |
| -21 | 2434345 | 1952-11-28 | 324.74 |
| -10 | 2437952 | 1962-10-14 | 325.28 |
| -3 | 2440220 | 1968-12-29 | 325.05 |
| -2 | 2440530 | 1969-11-04 | 324.08 |
| -1 | 2440835 | 1970-09-05 | 322.13 |
| 0 | 2441168 | 1971-08-04 | 319.68 |
| 1 | 2441476 | 1972-06-07 | 320.2 |
| 3 | 2442110 | 1974-03-03 | 321.25 |
| 5 | 2442750 | 1975-12-03 | 319.86 |
| 7 | 2443414 | 1977-09-27 | 319 |
| 8 | 2443740 | 1978-08-19 | 320.09 |
| 9 | 2444050 | 1979-06-25 | 320.48 |
| 12 | 2444990 | 1982-01-20 | 319.11 |
| 13 | 2445310 | 1982-12-06 | 318.59 |
| 14 | 2445638 | 1983-10-30 | 319.58 |
| 15 | 2445952 | 1984-09-08 | 321.33 |
| 16 | 2446275 | 1985-07-28 | 322.64 |
| 21 | 2447888 | 1989-12-27 | 323.14 |
| 22 | 2448211 | 1990-11-15 | 323.86 |
| 23 | 2448541 | 1991-10-11 | 324.78 |
| 24 | 2448857 | 1992-08-22 | 326.45 |
| 25 | 2449200 | 1993-07-31 | 328 |
| 26 | 2449515 | 1994-06-11 | 328 |
| 28 | 2450182 | 1996-04-08 | 328.88 |
| 29 | 2450510 | 1997-03-02 | 329 |
| 30 | 2450837 | 1998-01-23 | 328.44 |
| 31 | 2451163 | 1998-12-15 | 328.6 |
| 32 | 2451497 | 1999-11-14 | 328.86 |
| 33 | 2451824 | 2000-10-06 | 329.29 |
| 34 | 2452146 | 2001-08-24 | 328.79 |
| 35 | 2452480 | 2002-07-24 | 328.64 |
| 36 | 2452816 | 2003-06-25 | 328.14 |
| 37 | 2453141 | 2004-05-15 | 328.36 |
| 38 | 2453462 | 2005-04-01 | 329.21 |
| 39 | 2453799 | 2006-03-04 | 328.14 |
| 40 | 2454116 | 2007-01-15 | 327.36 |
| 41 | 2454451 | 2007-12-16 | 327.67 |
| 42 | 2454784 | 2008-11-13 | 325.91 |
| 43 | 2455106 | 2009-10-01 | 325.41 |
| 44 | 2455434 | 2010-08-25 | 326.18 |
| 49 | 2457067 | 2015-02-13 | 325.36 |
| 50 | 2457364 | 2015-12-07 | 325.14 |
| 51 | 2457710 | 2016-11-17 | 324.82 |
| 52 | 2458033 | 2017-10-06 | 324.17 |
| 53 | 2458360 | 2018-08-29 | 325.64 |
| 54 | 2458683 | 2019-07-18 | 326.46 |
| 55 | 2459003 | 2020-06-02 | 324.49 |
| 56 | 2459333 | 2021-04-28 | 324.17 |
| 57 | 2459657 | 2022-03-18 | 323.6 |
| 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. |