How "big" are the mathematical disciplines?

Question

This question may be difficult to answer, but is it possible to estimate the "size" of the individual mathematical disciplines; measures of size could be number of professionals dealing with it, the number of magazines and new theorems etc.? For instance, I usually consider analysis, algebra, and topology to be the three major branches of mathematics. But how many of the total number of mathematicians are dealing with each of these? My impression is that analysis is the largest discipline, but I could be wrong.

Answer 1

For a rough graphical representation see for example here and here.

(Related questions with interesting links can be found here and here and here.)