Change in OI vs Traded volume - Numbers are not matching

F&O
1

I am quite surprised with the data that i see on the chart for HDFCBANK JUNE FUTURE at 2025-06-06T07:36:00Z

There is sudden drop in the OI but the volume traded during that window is far less than the change in OI. so is that possible.

For candle at 13:09 the change in OI is almost 1M but volumes are in few thousands, how is that possible.

|Candle Time | Volume | OI | Change in OI|

|— | — | — | —|
|13:03 | 39,050 | 112,035,550 | | |13:06 | 62,700 | 112,027,850 | -7,700|
|13:09 | 45,100 | 111,017,500 | -1,010,350| |13:12 | 60,500 | 110,977,900 | -39,600|
| | | | |

HDFBANKC_JUN_FUT_OI_1
HDFBANKC_JUN_FUT_OI_1957×855 127 KB

HDFBANKC_JUN_FUT_OI_2
HDFBANKC_JUN_FUT_OI_2957×855 127 KB

2

OI data is not live, guess that is delayed by 1 to 3 mins from NSE itself, across brokers.

3

The chart is on 3 minutes and even if i sum previous 5 candles (so count last 15 minutes) still those number are not adding up.
And for previous candles OI did change so the max delay is 3 minutes.

Do you have any information how NSE calculates the OI?
Is it clearing participant level or at individual trader level?

4

At market level if you are referring to OI which is displayed on feed.