As he started becoming more and more popular starting from 1976, the year Annakkili was released he started scoring more and more movies each year. I wanted to plot this in a chart and that is what you see below.
The last year he had one of his multi film hits around same time was in 1993. This is when all the so called big banner directors deserted him. By this time he had already scored music to ~ 600 films. The right hand side scale shows the cumulative # of movies, which hits a plateau around the same time. In my opinion there is a distinct sound that appears in his songs for a given period of time, which is approximately 2-3 years, after which you will see a paradigm change in the way he scores the music. More about this later with examples.
I recently discovered some great blogs that analyze Raja's music thread bare. You can see them on the side bar amongst the blogs I follow.