If you mean how many unique users... you can't. Thread views does not equal unique views. There is no way to gauge unique user views on a thread... but as I stated previously, the "10% rule" is a good rule of thumb that usually proves close to the mark. I would guess that maybe 200 users have viewed your thread, and 20 have found it useful.
As Confucius stated, 20 reputation for a single thread is a lot. I spend 20+ hours on a single exploration/recording/video editing at times, and get much less.