Knowing the total index value for every cell, we can estimate a median index for a borough in order to see a more general picture. The London Plan describes a division between Inner and Outer London, Inner London being a territory with higher population and density of jobs. The Central Activities Zone (CAZ), the central part of Inner London, is where the highest index values can be found. These territories have the "largest concentration of London's financial and globally-oriented business services. Almost a third of all London jobs are based there" (2.44).
The CAZ is also a cultural and retail centre of the city. The territories outside the CAZ can't compete with its density of cultural, retail and social infrastructure - so we couldn't expect the peak index values to be anywhere else. The other main feature of the CAZ, aside from that of the high infrastructure provision level, is that its population density is significantly lower than in the areas of Inner London surrounding it. This makes it a central business district with a high everyday commute level.