JUL series Day-13 Nifty=5193 (-4)
In this JUL series we have 5 UP ,1 NO change and 7 DOWN days as follows:
UNUUUDDUDDDDD
Now the Expiry zone has continued to be (5100~5300).
Though the loss appears to be very low,the impact is severe because the gapup was good in the morning.
OI is rather mixed in both CALL window & PUT window .
The significant additions/sheddings in this zone ,are indicated in the chart.
There was more than 1M
OI at 5300CE today alone whereas it was
0.68M 5300PE strike.
Premium eating was seen in both PE and CE options because both have lost
values except 5200PE upwards.
THETA (time decay):
The option's theta is a measurement of the option's time decay.
The theta measures the rate at which options lose their value,
specifically the time value, as the expiration date draws nearer.
Generally expressed as a negative number, the theta of an option
reflects the amount by which the option's value will decrease every day.
(courtesy:theoptionguide.com)