Figure 7.4.7. Estimated modulation frequencies in Bach’s Well Tempered Clavier and the piano sonatas of Haydn, Mozart, and Beethoven. The left column indicates the directed chromatic interval of root motion from source key to target key. (For example, a modulation from F major to G major or B minor to Cs major is represented by the number two 2.) Under each composer’s name, the “min” and “maj” columns refer to the modality of the target key. The two or three largest values in each column are in boldface.