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The TeV blazar PKS 2155--304 was the subject of an intensive 2 week opticaland near-infrared observing campaign in 2004 August with the CTIO 0.9mtelescope. During this time, simultaneous X-ray data from RXTE were alsoobtained. We compare the results of our observations to the results from twoprevious simultaneous multiwavelength campaigns on PKS 2155-304. We concludethat the correlation between the X-ray and UV/optical variability is strongestand the time lag is shortest (only a few hours) when the object is brightest.As the object becomes fainter, the correlations are weaker and the lags longer,increasing to a few days. Based on the results of four campaigns, we findevidence for a linear relationship between the mean optical brightness and lagtime of X-ray and UV/optical events. Furthermore, we assert that this behavior,along with the different multiwavelength flare lag times across different fluxstates is consistent with a highly relativistic shock propagating down the jetproducing the flares observed during a high state. In a quiescent state, thevariability is likely to be due to a number of factors including both the jetand contributions outside of the jet, such as the accretion disk.

New Multiwavelength Observations of PKS 2155-304 and Implications for the Coordinated Variability Patterns of Blazars