The estimated formation time of 75% of the stellar mass (in terms of lookback time, τ ₇₅) for each galaxy in our massive, high-redshift sample. The points are colored by redshift, where we bin galaxies into bins of stellar mass, with each bin having an equal number of sources. The open black squares show the median of each bin, with the error bars denoting the 18% and 84% spread. There is a slight trend with τ ₇₅ with respect to the observed stellar mass, with galaxies of larger mass forming the bulk of their stars at an earlier time, but this is not significant with the constraints on these quantities from the current data. Due to the difficulty constraining SFHs with only photometry, we note there exist large errors associated with τ ₇₅. SFHs are often difficult to constrain based on photometry alone, with follow-up spectroscopy often necessary to properly disentangle the underlying stellar populations. Furthermore, at very high redshifts, our sample is small (of order a few galaxies at z > 7); larger surveys will be able to provide the sample sizes needed to properly infer trends with redshift.