@subsubheading Description

Monthly numbers of sunspots, as from the World Data Center, aka SIDC. This
is the version of the data that may occasionally be updated when new counts
become available.

@subsubheading Format

@table @code
@item month
Month of the observation.
@item sunspots
Number of sunspots.
@end table

@subsubheading Source

WDC-SILSO, Solar Influences Data Analysis Center (SIDC), Royal Observatory
of Belgium, Av. Circulaire, 3, B-1180 BRUSSELS.
Currently at @url{http://www.sidc.be/silso/datafiles}.

@subsubheading Examples

@example
@INCLUDE_DATASET_EXAMPLE_SCRIPT{sunspot_month_1.m}
@end example
