Series | Conventional time interval | ESAI time interval |

monthly sunspot areas (Greenwich general system) | 1874-1976 | 1821-1989 |

yearly sunspot areas (Greenwich general system) for N- and S- hemispheres | 1874-1976 | 1821-1994 |

yearly mean latitudes of sunspots for N- and S- hemispheres | 1874-1976 | 1854-1985 |

yearly polar faculae numbers (Mt.Wilson general system) for N- and S- hemispheres | 1906-1991 | 1837-1999 |

yearly Wolf numbers (International general system) | 1700-2002 | 1090-2002 |

yearly polar faculae numbers (Mt.Wilson general system) | 1906-1991 | 1705-1999 |

ESAI monthly sunspot areas (1821-1989), yearly sunspot areas
(1821-1994) and yearly mean latitudes of sunspots (1854-1985)
were created by compilation of pre-Greenwich observational
data sets (by Schwabe, Carrington, De La Rue, Sporer) and
post-Greenwich observations (Gnevysheva) to Greenwich general
system.
*Ref: Nagovitsyn Yu. A. The series of total sunspot
area index in the Greenwich general system (1821-1989). //
"Solnechnye dannye. 1995-1996" Bulletin. PP.38-48. 1997. (in
Russian).*

Yearly polar faculae numbers were constructed by synthesis of
different data series: Mt.Wilson, Greenwich, Lyon, Kodaykanal,
Tokyo, Zurich, Kislovodsk observations of polar facula and
observations of polar coronal structures during solar
eclipses.
*Ref: Nagovitsyn Yu.A. A synthetic series of yearly
means of polar faculae numbers for 1847-1979. // "Solnechnye
dannye" Bulletin. No 8. PP. 88-95. 1988. (in Russian).*

Series of yearly Wolf numbers for 1090-2002. Based on
Krylov-Bogolyubov's approach to the description of weakly
nonlinear oscillatory processes, the nonstationary
frequency-amplitude structure of the Wolf numbers (1700-1995)
was analyzed. Using the nonlinear description and well-known
Schove's data on the epochs of extrema of 11-yr solar cycles
in the past, the yearly average Wolf numbers in 1090-1699 were
reconstructed.
*Ref. Nagovitsyn Yu.A. A nonlinear mathematical
model for the Solar cyclicity and prospects for reconstructing
the Solar activity in the Past.// Astronomy Letters. Vol. 23.
No. 6. PP. 742-748. 1997.*

Yearly polar faculae numbers for 1705-1999 were created by
procedure similar to one used for the Wolf numbers reconstruction
(in assumption that 11-yr cycles of polar faculae develop in
exact antiphase to sunspot cycles).
*Ref. Nagovitsyn Yu.A. The Solar cyclicity on the large time scale.
// Proceedings of conference "New cycle of Solar activity:
observational and theoretical aspects". Pulkovo. 1998.
PP.321-324 (in Russian).*

**GRAPHICS**. The figures show variations of the mentioned above indices.
Time intervals of ESAI-extension of solar activity parameters
are marked by the blue colour.