Baseline Estimation 

Import the recent sunspot activity.

In[1]:=

X data = WolframAlpha[ "sunspot", {{"SunspotsPartialTimeSeries:SpaceWeatherData", 1}, "TimeSeriesData"}][[All, 2]];

Estimate and visualize the background of the signal.

In[2]:=

X bg = EstimatedBackground[data, 10];

In[3]:=

X ListLinePlot[{data, bg}, AspectRatio -> 1/3, ImageSize -> Medium]

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Subtract the background from data.

In[4]:=

X ListLinePlot[data - bg, AspectRatio -> 1/3, ImageSize -> Medium]

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