When plotted on the 1977 charts, David's length-for-age is at the 5th percentile while his stature-for-age is at the 10th percentile. When changing from recumbent length to stature, there appeared to be an upward shift in stature. This could be misinterpreted as an improvement in linear growth, when it is actually an artifact of the 1977 charts. This disjunction occurred in part because recumbent length data for the 1977 charts were obtained from the Fels Longitudinal Study while stature data were obtained from NCHS data.
In the new CDC growth charts, there is no longer a disjunction between length and stature because recumbent length and stature data were taken from the same child. When David's measurements are plotted on the CDC Growth Charts, he is at the 10th percentile on both the length-for-age and stature-for-age charts.