Underlying = 100 K = 90
1 year Put at K is trading 5. What's the approximate delta of the put?
Underlying = 100 K = 90
1 year Put at K is trading 5. What's the approximate delta of the put?
assuming you don't have a black scholes pricer, or don't want to rely on a pricer... the following book contains many of the "rule of thumbs" that you are seeking: