Period length over time for Mira stars

These period diagrams is based on the O-C diagrams at http://var.saaf.se/mirainfooc.php and calculated with data from AAVSO, AFOEV, VSOLJ, BAAVSS, ASAS-SN and DASCH and various published maxima. The diagrams shows the development over time of the stars mean period or cycle length.
The difference between the mean period and the period at a certain time can be calculated as the slope of an O-C diagram at that time. To get the O-C diagram more smooth and thus the period less jumpy a moving average O-C for each cycle was first calculated. The moving average is the mean of the O-C for the current cycle together with 3 O-C values before and after the current.
The period for cycle i was then calculated as: Mean period + (avg O-Ci+1 - avg O-Ci-1) / 2.

Each diagram is also clickable to get a table with the underlying data.



Constellations
And - CMi
Cap - Cyg
Del - Hyi
Ind - Ori
Pav - Vul



Delphinus
R Del
Mean period: 285.22, Mean epoch: 2444077.3
GCVS period: 285.07, GCVS epoch: 2444091
GCVS spectral type: M5e-M6e


S Del
Mean period: 278.15, Mean epoch: 2444865.2
GCVS period: 277.75, GCVS epoch: 2444887
GCVS spectral type: M5e-M8


T Del
Mean period: 331.84, Mean epoch: 2443288.5
GCVS period: 332.02, GCVS epoch: 2443296
GCVS spectral type: M3e-M6e


V Del
Mean period: 528.83, Mean epoch: 2440961.1
GCVS period: 533.51, GCVS epoch: 2441065
GCVS spectral type: M4e-M6e


X Del
Mean period: 281.48, Mean epoch: 2441559.6
GCVS period: 281.04, GCVS epoch: 2441551
GCVS spectral type: M4e-M6e


Y Del
Mean period: 469.24, Mean epoch: 2442740.2
GCVS period: 468.4, GCVS epoch: 2442707
GCVS spectral type: M8e


Z Del
Mean period: 304.69, Mean epoch: 2442338.2
GCVS period: 304.48, GCVS epoch: 2442317
GCVS spectral type: S5,2.5e-S7,2e:


RU Del
Mean period: 260.24, Mean epoch: 2438909.1
GCVS period: 260.58, GCVS epoch: 2438900
GCVS spectral type: M3


RX Del
Mean period: 185.44, Mean epoch: 2442293.0
GCVS period: 185.63, GCVS epoch: 2442320
GCVS spectral type: M2e


SS Del
Mean period: 194.37, Mean epoch: 2436524.3
GCVS period: 194.59, GCVS epoch: 2436521
GCVS spectral type:


Dorado
SU Dor
Mean period: 235.76, Mean epoch: 2440742.6
GCVS period: 235.86, GCVS epoch: 2440741
GCVS spectral type:


Draco
R Dra
Mean period: 245.75, Mean epoch: 2444786.5
GCVS period: 245.6, GCVS epoch: 2444779
GCVS spectral type: M5e-M9eIII


T Dra
Mean period: 421.91, Mean epoch: 2443967.8
GCVS period: 421.62, GCVS epoch: 2443957
GCVS spectral type: C6,2e-C8,3e(N0e)


U Dra
Mean period: 317.69, Mean epoch: 2444395.9
GCVS period: 316.13, GCVS epoch: 2444290
GCVS spectral type: M6e-M8


V Dra
Mean period: 278.57, Mean epoch: 2444460.4
GCVS period: 278.33, GCVS epoch: 2444451
GCVS spectral type: M4e


W Dra
Mean period: 271.32, Mean epoch: 2442414.2
GCVS period: 278.6, GCVS epoch: 2442176
GCVS spectral type: M3e-M4e


X Dra
Mean period: 257.47, Mean epoch: 2444177.7
GCVS period: 257.33, GCVS epoch: 2444167
GCVS spectral type: M5e:


Y Dra
Mean period: 325.92, Mean epoch: 2444488.2
GCVS period: 325.79, GCVS epoch: 2444448
GCVS spectral type: M5e


RT Dra
Mean period: 278.73, Mean epoch: 2435467.8
GCVS period: 279.41, GCVS epoch: 2435494
GCVS spectral type: M5


RV Dra
Mean period: 208.58, Mean epoch: 2443533.5
GCVS period: 208.14, GCVS epoch: 2443526
GCVS spectral type: M1e-M3e


SV Dra
Mean period: 256.27, Mean epoch: 2443735.6
GCVS period: 256.24, GCVS epoch: 2443714
GCVS spectral type: M7e


ZZ Dra
Mean period: 269.64, Mean epoch: 2441187.0
GCVS period: 267.9, GCVS epoch: 2441209
GCVS spectral type: M7e


Equuleus
R Equ
Mean period: 260.56, Mean epoch: 2442927.8
GCVS period: 260.76, GCVS epoch: 2442921
GCVS spectral type: M3e-M4e


RR Equ
Mean period: 270.98, Mean epoch: 2443709.3
GCVS period: 271.3, GCVS epoch: 2443716
GCVS spectral type:


Eridanus
T Eri
Mean period: 252.53, Mean epoch: 2442097.8
GCVS period: 252.29, GCVS epoch: 2442079
GCVS spectral type: M3e-M5e


U Eri
Mean period: 274.36, Mean epoch: 2440100.7
GCVS period: 274.91, GCVS epoch: 2440110
GCVS spectral type: M4e


W Eri
Mean period: 376.10, Mean epoch: 2440314.6
GCVS period: 376.63, GCVS epoch: 2440345
GCVS spectral type: M7e-M9


Fornax
R For
Mean period: 388.35, Mean epoch: 2441941.5
GCVS period: 388.73, GCVS epoch: 2441974
GCVS spectral type: C4,3e(Ne)


Gemini
R Gem
Mean period: 369.97, Mean epoch: 2443339.6
GCVS period: 369.91, GCVS epoch: 2443325
GCVS spectral type: S2,9e-S8,9e(Tc)


S Gem
Mean period: 292.96, Mean epoch: 2443580.1
GCVS period: 293.23, GCVS epoch: 2443578
GCVS spectral type: M4e-M8e


T Gem
Mean period: 287.59, Mean epoch: 2444693.9
GCVS period: 287.79, GCVS epoch: 2444710
GCVS spectral type: S1.5,5e-S9,5e


V Gem
Mean period: 275.04, Mean epoch: 2442700.4
GCVS period: 274.8, GCVS epoch: 2442694
GCVS spectral type: M4(S)e-M8


X Gem
Mean period: 264.06, Mean epoch: 2443513.5
GCVS period: 264.16, GCVS epoch: 2443553
GCVS spectral type: M5e-M8e(Tc:)


ST Gem
Mean period: 245.92, Mean epoch: 2443828.2
GCVS period: 246.23, GCVS epoch: 2443854
GCVS spectral type: M5e-M9e


VV Gem
Mean period: 252.76, Mean epoch: 2435521.4
GCVS period: 252.9, GCVS epoch: 2435520
GCVS spectral type:


WZ Gem
Mean period: 332.23, Mean epoch: 2438067.5
GCVS period: 330.8, GCVS epoch: 2438048
GCVS spectral type: M3e


ZZ Gem
Mean period: 316.07, Mean epoch: 2433977.8
GCVS period: 317, GCVS epoch: 2433999
GCVS spectral type: C5,3e(Ne)


BP Gem
Mean period: 244.48, Mean epoch: 2443921.4
GCVS period: 246.5, GCVS epoch: 2443955
GCVS spectral type: M8e


BR Gem
Mean period: 155.67, Mean epoch: 2439888.4
GCVS period: 155.8, GCVS epoch: 2439909
GCVS spectral type:


Grus
R Gru
Mean period: 332.67, Mean epoch: 2440993.7
GCVS period: 331.96, GCVS epoch: 2440957
GCVS spectral type: M5e-M7II-IIIe


S Gru
Mean period: 400.95, Mean epoch: 2440590.1
GCVS period: 401.51, GCVS epoch: 2440608
GCVS spectral type: M5e-M8IIIe


T Gru
Mean period: 136.72, Mean epoch: 2442082.8
GCVS period: 136.49, GCVS epoch: 2442072
GCVS spectral type: M1Iae-M2Ibe


Hercules
R Her
Mean period: 318.12, Mean epoch: 2445079.7
GCVS period: 318.14, GCVS epoch: 2445058
GCVS spectral type: M6e


S Her
Mean period: 307.64, Mean epoch: 2445034.8
GCVS period: 307.28, GCVS epoch: 2445054
GCVS spectral type: M4,Se-M7.5,Se


T Her
Mean period: 164.92, Mean epoch: 2445298.9
GCVS period: 164.98, GCVS epoch: 2445306
GCVS spectral type: M2.5e-M8e


U Her
Mean period: 405.77, Mean epoch: 2444983.8
GCVS period: 406.1, GCVS epoch: 2444994
GCVS spectral type: M6.5e-M9.5e


W Her
Mean period: 279.95, Mean epoch: 2445044.1
GCVS period: 280.03, GCVS epoch: 2445059
GCVS spectral type: M3e-M5e


RS Her
Mean period: 219.47, Mean epoch: 2445160.9
GCVS period: 219.7, GCVS epoch: 2445194
GCVS spectral type: M4e-M8:


RT Her
Mean period: 297.79, Mean epoch: 2445094.7
GCVS period: 298.08, GCVS epoch: 2445104
GCVS spectral type: M4e


RU Her
Mean period: 486.01, Mean epoch: 2444933.2
GCVS period: 484.83, GCVS epoch: 2444899
GCVS spectral type: M6e-M9


RV Her
Mean period: 205.53, Mean epoch: 2445163.0
GCVS period: 205.23, GCVS epoch: 2445143
GCVS spectral type: M2e


RY Her
Mean period: 221.41, Mean epoch: 2445203.3
GCVS period: 221.47, GCVS epoch: 2445211
GCVS spectral type: M4e-M6e


RZ Her
Mean period: 328.70, Mean epoch: 2445143.6
GCVS period: 329.05, GCVS epoch: 2445143
GCVS spectral type: M5e-M6e


SS Her
Mean period: 106.91, Mean epoch: 2445228.3
GCVS period: 107.36, GCVS epoch: 2445209
GCVS spectral type: M0e-M5e


SV Her
Mean period: 238.52, Mean epoch: 2445142.7
GCVS period: 238.99, GCVS epoch: 2445143
GCVS spectral type: M5e


SY Her
Mean period: 116.85, Mean epoch: 2445237.5
GCVS period: 116.91, GCVS epoch: 2445248
GCVS spectral type: M1e-M6e


TV Her
Mean period: 304.38, Mean epoch: 2445232.5
GCVS period: 304.28, GCVS epoch: 2445254
GCVS spectral type: M4e


UV Her
Mean period: 342.67, Mean epoch: 2442992.9
GCVS period: 341.95, GCVS epoch: 2442934
GCVS spectral type: M6e-M6.5e


UZ Her
Mean period: 263.88, Mean epoch: 2442200.3
GCVS period: 263.74, GCVS epoch: 2442175
GCVS spectral type: M5e


VV Her
Mean period: 383.81, Mean epoch: 2439911.4
GCVS period: 385.64, GCVS epoch: 2439959
GCVS spectral type: M7


VY Her
Mean period: 300.55, Mean epoch: 2441908.0
GCVS period: 300.38, GCVS epoch: 2441914
GCVS spectral type: M5e:


WX Her
Mean period: 182.70, Mean epoch: 2430554.5
GCVS period: 186, GCVS epoch: 2430533
GCVS spectral type:


WZ Her
Mean period: 248.89, Mean epoch: 2427901.8
GCVS period: 247.8, GCVS epoch: 2427900
GCVS spectral type:


XZ Her
Mean period: 171.58, Mean epoch: 2433896.5
GCVS period: 171.69, GCVS epoch: 2433887
GCVS spectral type: M0


AE Her
Mean period: 249.15, Mean epoch: 2445138.0
GCVS period: 248.99, GCVS epoch: 2445149
GCVS spectral type: M4e


AS Her
Mean period: 268.66, Mean epoch: 2440719.6
GCVS period: 269.14, GCVS epoch: 2440750
GCVS spectral type: M2e


AZ Her
Mean period: 270.11, Mean epoch: 2436803.2
GCVS period: 268.92, GCVS epoch: 2436782
GCVS spectral type: M4


CF Her
Mean period: 307.55, Mean epoch: 2434947.4
GCVS period: 306.2, GCVS epoch: 2434902
GCVS spectral type: M0


DF Her
Mean period: 333.98, Mean epoch: 2436338.5
GCVS period: 337.7, GCVS epoch: 2436379
GCVS spectral type: M6e


DN Her
Mean period: 226.94, Mean epoch: 2431592.5
GCVS period: 226, GCVS epoch: 2431575
GCVS spectral type:


DO Her
Mean period: 213.74, Mean epoch: 2440317.6
GCVS period: 216.28, GCVS epoch: 2440391
GCVS spectral type:


DS Her
Mean period: 263.40, Mean epoch: 2440435.6
GCVS period: 263.43, GCVS epoch: 2440446
GCVS spectral type:


FU Her
Mean period: 212.29, Mean epoch: 2433529.6
GCVS period: 212.4, GCVS epoch: 2433529
GCVS spectral type:


NP Her
Mean period: 434.48, Mean epoch: 2439675.4
GCVS period: 448, GCVS epoch: 2439643
GCVS spectral type: C6,3e(N)


Horologium
R Hor
Mean period: 404.43, Mean epoch: 2441457.3
GCVS period: 407.6, GCVS epoch: 2441494
GCVS spectral type: M5e-M8eII-III


T Hor
Mean period: 217.52, Mean epoch: 2441952.9
GCVS period: 217.6, GCVS epoch: 2441957
GCVS spectral type: M5IIe


U Hor
Mean period: 350.68, Mean epoch: 2434707.6
GCVS period: 348.4, GCVS epoch: 2434638
GCVS spectral type: M6IIIe


Hydra
R Hya
Mean period: 421.66, Mean epoch: 2443887.7
GCVS period: 388.87, GCVS epoch: 2443596
GCVS spectral type: M6e-M9eS(Tc)


S Hya
Mean period: 256.89, Mean epoch: 2443506.5
GCVS period: 256.63, GCVS epoch: 2443509
GCVS spectral type: M4e-M8.0e


T Hya
Mean period: 288.94, Mean epoch: 2441933.1
GCVS period: 298.7, GCVS epoch: 2441975
GCVS spectral type: M3e-M9:e


X Hya
Mean period: 300.60, Mean epoch: 2441076.5
GCVS period: 301.1, GCVS epoch: 2441060
GCVS spectral type: M7e-M8.5e


RR Hya
Mean period: 342.13, Mean epoch: 2439144.9
GCVS period: 343.49, GCVS epoch: 2439212
GCVS spectral type: M3.0e-M8e


RS Hya
Mean period: 335.67, Mean epoch: 2439159.2
GCVS period: 338.6, GCVS epoch: 2439169
GCVS spectral type: M6e


RU Hya
Mean period: 332.06, Mean epoch: 2443147.8
GCVS period: 331.5, GCVS epoch: 2443162
GCVS spectral type: M6e-M8.8e


ST Hya
Mean period: 303.24, Mean epoch: 2440259.2
GCVS period: 304.75, GCVS epoch: 2440282
GCVS spectral type: Me


UZ Hya
Mean period: 262.59, Mean epoch: 2442572.1
GCVS period: 260.95, GCVS epoch: 2442527
GCVS spectral type: M4e