I'm setting up a spreadsheet to monitor trades using links to thinkorswim. For RUT I see that the OPRA symbol changes from RUR to RUW when the strikes goes from 390 to 400. Why is that?
Come on man use your head. All there is a finite number of stikes if you can list if you use only the letters in the alphabet to code the month then strike. The underlying has moved so much since DEC got listed they have more then those 2 root symbols you listed