SGX breadth sucks

The graph below shows STI (blue) with the daily number of SGX stocks making 1 month highs (the scattered dots) since the start of the March rally. These are smoothed as a 1-month moving average (red line). Sub 20c stocks are excluded.

The divergence since Aug is too clear. How long can this continue? Either the STI must go down, or the number of stocks making highs must go up.

I did not find this indicator useful in predicting past market tops. So it is only to show what is happening now.