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The association of starspots with magnetic fields leads to an expectationthat quantities which correlate with magnetic field strength may also correlatewith {starspot} coverage. Since younger stars spin faster and are moremagnetically active, assessing whether {starspot} coverage correlates withshorter rotation periods and stellar youth tests these principles. Here weanalyze the {starspot} covering fraction versus stellar age for M{-}, G{-},K{-}, and F{-}type stars based on previously determined variability androtation periods of over 30,000 {\textit{Kepler}} main-sequence stars. Wedetermine the correlation between age and variability using single and dualpower law best fits. We find that {starspot} coverage does indeed decrease withage. Only when the data {are} binned in an effort to remove the effects ofactivity cycles of individual stars, do statistically significant power lawfits emerge for each stellar type. {Using bin averages,} we then find that the{starspot} covering fraction scales with the {X}-ray to bolometric ratio to thepower $\lambda$ with {$0.22\pm 0.03 < \lambda < 0.32\pm 0.09$} for {G-type}stars of rotation period below 15 days and for the full range of F{-} andM{-type} stars. For K{-}type stars, we find two branches of $\lambda$ separatedby variability bins, with the lower branch showing nearly constant starspotcoverage and the upper branch {$\lambda \sim 0.35\pm 0.04$.} G{-}type starswith periods longer than $15$ days exhibit a transition to steeper power law of{$ \lambda \sim 2.4 \pm 1.0$.} The potential connection to previousrotation-age measurements suggesting a magnetic breaking transition at thesolar age, corresponding to period of $24.5$ is also of interest.

Determination of Starspot Covering Fraction as a function of Stellar Age from Observational Data