Thanks Rich,
I got a view of a right chart at your blog since I can not draw that at my system without correct data. As opening a put, I think it is still not a good time now as I said previous days that we would meet a period low at pm Tuesday but should open a put at end of May. (selected from Rich's blog)

Black Monday did not come as I thought last week, but fortunately the period low came at right time and people can open a call and take profit now. That is a good job for day trading. In day trading, relative position is important.