Question: What is the time fluctuation in sunspot numbers?
About the article "Astronomy", section "Solar astronomy".

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When the time traveling antihero Cable takes over the New Mutants and turns them into the paramilitary group X-Force, Sunspot parts ways with the team.
During this time Sunspot is tutored by Gideon of the Externals, an old business partner of Roberto's father (who has since died).
Suspecting Sunspot to be a fellow External, he takes Sunspot under his wing.
Gideon ends up experimenting on Sunspot, granting him new powers such as flight and the ability to fire blasts of solar energy.
For a time Sunspot becomes lost in a space-time continuum after interfering with the teleportation powers of Locus.
During this time, a villain called Reignfire comes onto the scene, showing a remarkable similar appearance to Sunspot. 
In this reality, Sunspot is shown as the leader of the Gene Nation. 
The Wolf number (also known as the International sunspot number, relative sunspot number, or Zürich number) is a quantity that measures the number of sunspots and groups of sunspots present on the surface of the sun.
The idea of computing sunspot numbers was originated by Rudolf Wolf in 1848 in Zurich, Switzerland and, thus, the procedure he initiated bears his name (or place).
The combination of sunspots and their grouping is used because it compensates for variations in observing small sunspots.
This number has been collected and tabulated by researchers for over 150 years.
They have found that sunspot activity is cyclical and reaches its maximum around every 9.5 to 11 years (note: Using data from SIDC for the last 300 years and running a FFT function on the data gives an average maximum at 10.4883 years/cycle).
This cycle was first noted by Heinrich Schwabe in 1843.
The relative sunspot number formula_1 is computed using the formula (collected as a daily index of sunspot activity):  formula_2 where  formula_3 is the number of individual spots,  formula_4 is the number of sunspot groups, and  formula_5 is a factor that varies with location and instrumentation (also known as the "observatory factor" or the "personal reduction coefficient" formula_6).  
In "What if Some of the X-Men Had Stayed In Asgard?
", Sunspot is one of the X-Men and New Mutants members who choose to remain in Asgard.
When Hela attacks Storm due to Loki's intrigues, Sunspot rushes to aid Storm, only to have his life taken away by the death goddess before he can even land a blow on her. 
The earliest surviving record of sunspot observation dates from 364 BC, based on comments by Chinese astronomer Gan De in a star catalogue.
By 28 BC, Chinese astronomers were regularly recording sunspot observations in official imperial records.
The first clear mention of a sunspot in Western literature, around 300 BC, was by the ancient Greek scholar Theophrastus, student of Plato and Aristotle and successor to the latter.
A more recent sunspot observation was made on 17 March 807 AD by the Benedictine monk Adelmus, who observed a large sunspot that was visible for eight days; however, Adelmus incorrectly concluded he was observing a transit of Mercury.
A large sunspot was also seen at the time of Charlemagne's death in 813 AD.
Sunspot activity in 1129 was described by John of Worcester, and Averroes provided a description of sunspots later in the 12th century; however, these observations were also misinterpreted as planetary transits, until Galileo gave the correct explanation in 1612.