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tokens: we sample 10,000 parameter combinations and generate one random light curve with the time sampling of the observed Keck data (∼30 nights of historical data and four nights of 2019 data) for each parameter set. We present the complementary cumulative distribution function (CCDF, or 1—CDF) of these 10,000 light curves in Figure 5 in the form of the median CDF and 1, 2, and 3 σ credible intervals. Figure 5. Top panel: comparison of the complementary cumulative distribution function (CCDF) of the observed data (historical data and 2019 data; black) and the median CCDF (dashed blue line) and the 1, 2, and 3 σ contours calculated from 10,000 simulations. The simulations were drawn from the posterior in Witzel et al. ( 2018 ). The dashed section of the observed CCDF represents flux densities that occurred only during the brightest flux excursion on 2019 May 13. These simulations show that if we repeated the entire experiment with the time sampling of 30 historical nights of Keck observations 10,000 times, then the probability of observing a single night with flux levels as high as 6 mJy is less than 0.3%. Bottom panel: the same as for the top panel but contours determined from simulations based only on the time sampling of the four nights in 2019. Because three of the four nights have elevated Sgr A* flux levels, if an experiment with four nights of observations were repeated 10,000 times, the probability of observing Sgr A* flux levels similar to the nights in 2019 would be less than 0.05%. Based on simulations drawn from the Sgr A* flux model, we can compute the probability of observing the light curves presented here. The simulations show that if we repeated our experiment 10,000 times with the time sampling of the 30 nights of historical Keck observations (from 2005 to 2013) of Sgr A*, and including the 2019 nights, there is a 0.3% probability that we observe a single night with flux levels as high as seen on 2019 May 13. These simulations are the most consistent with our current observations because they have very similar noise properties, observed duration, and timing. If we also include VLT nights for a total of over 130 nights, then the probability is less than 1.5% to observe flux values higher than 6.18 mJy on a single night. We can also consider the probability of randomly drawing 4 light curves similar to the observations in 2019. This probability is considerably lower at less than 0.05%. We also note that we have only observed the decay of the light curve on 2019 May 13, which suggests the actual maximum was likely even higher (Figure 3 ). Here we examine two possibilities for explaining the very unusual brightness and variation of Sgr A* observed this year: (1) the statistical models need to be changed or updated, and (2) there is a physical change in the accretion activity of Sgr A*. Based on the statistical model of Witzel et al. ( 2018 ), with the four nights of observations, there is a probability of less than 0.05% to