BSE (Bombay Stock Exchange)- Bet on Financialization?

I was intrigued by sustained price erosion for BSE in last couple of months. Here’s is the plot of BSE average price and average daily volume:
image

Pls note that I’ve not take first month of listing (Feb’17) in this chart as volumes were unusually high.
Referring to this post :

The spike in volume is from November 2017 as can be seen in the graph, and price continued to be coming down unabated since Aug 2017. So there’s something more than the unlocked pre-IPO shares here.
Regarding buyback, BSE is steadily buying back its shares (roughly 15k per day since Feb 2, 2018) which is only 7% of the daily average volume, which, in my opinion, should not impact price trend much.
Any comment from technical point of view by veterans?
Disc: Invested, and added in last one week.