Owing to inductive effects, the basicity of an amine might be expected to increase with the number of alkyl groups on the amine.  Correlations are complicated owing to the effects of solvation which are opposite the trends for inductive effects. Solvation effects also dominate the basicity of aromatic amines (anilines). For anilines, the lone pair of electrons on nitrogen delocalizes into the ring, resulting in decreased basicity.  Substituents on the aromatic ring, and their positions relative to the amino group, also affect basicity as seen in the table.