The criterion seems to work well in Year 5 and 6 in Japan and Australian school 2 where the number of students classified as SR is comparatively high. In these two groups the success rate of students who showed stable relational SR performance on the three groups of number sentences was almost 20% higher in obtaining a score 1 on the question involving literal symbols than the general success rate the strength of connection is not as rate of the SR performers on the number sentences is only 10% higher than the general success rate ceiling effects begin to emerge in the year 7 in Japan and in Australian school 2 where 88% and 82% respectively of students in Year 7 were able to deal successfully score 1 with the question involving literal symbols.