change in OI more than volume

in option chain on NSE india some strikes shows change in open interest greater than volume. How is that, because change in open interest could be max. equal to volume if all trades consider new.

Can u post snapshot where you saw that?

volume is given as no of lots and chg in oi as quantity.

if volume is given as 5 in a nifty strike, it implies 5*75 = 375

so at any point chg in oi cannot be greater than vol.

thanks mohan.sic for quick reply
as you said it is possible but column title does not mentioned this difference

I figured this one out

Its simple maths, volume is additive only whereas Change in OI is subtractive for OI that close.

so in the morning, say OI was increasing along with volume.
Now both have say, COI 10k and VOL 10k.

Now as positions close, OI starts dropping and can approach 0.
After that COI will start registering Negative OI values.
This means OI which was opened on previous days is also closing positions.

Anyway, OI starts from series start and will start from 0 and go +ve (no reset)
Volume will be 0 at day open and go only +ve (resets to 0 at each day open)
COI can have a range of -ve to +ve (resets to 0 at each day open)

So COI can be 0, same time its volume will be 100k.

Thanks travi for explanation

Mohan is correct.

The other was mentioned by Mohan. That's also part of it.
OI & COI is in terms of total Quantity while Volume is in total lots.

So if one fresh lot of option is written, Volume will be 1 and COI will be 40 at day start.
so in this case COI > Volume.
but volume is only +ve increment whereas OI/COI can be subtractive.
Don't look at snapshot, observe the variation over the day.