The benchmark Sensex and Nifty are on course for a fourth straight monthly advance, each up over 3 per cent so far this month.
While the headline indices remain firm, market breadth has thinned, with more stocks declining than rising.
If this trend holds through the final trading session, June will be the first month since February to log negative market breadth.
The advance/decline ratio has slipped below 1, even as the Nifty Smallcap 100 and Midcap 100 have gained 3.4 per cent and 6 per cent, respectively. The Nifty Microcap 250 has underperformed, rising just 2.14 per cent.

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