Figure 1. Moving averages of the CD4 slope and the viral setpoint.

The figure reveals considerable short-term fluctuations over a steady trend towards steeper CD4 slopes (A) and higher setpoints (B). Each point represents the averaged value of 50 patients and is dated to their mean date of confirmed infection. The window of averaging moved along the list of patients sorted according to the date of confirmed infection: the first point represents the average of the first 50 patients, the second point represents the average calculated over the second through the 51^st patient, etc. The same datasets were used as in the multivariate regression analyses, i.e. outliers below the 5% and above the 95% quantiles were removed from the set of CD4 slopes.