Left: AL residuals with respect to G magnitude. Right: Histogram of the AL residuals in the interval [–10,10] mas. The tails (not visible in the histogram) contain 7304observations (~0.4% of the total number of observations published in Gaia DR2) for which the residuals are greater than 10 mas or smaller than –10 mas. The mean of the residuals in AL is 0.05 mas and the standard deviation is 2.14 mas.