Telephone marketing pests cold calling phone calls - can be stopped!

I thought you might be interested to know that I have found a way that has worked to stop all those very annoying, harrasing telephone calls that are not from friends around dinner time @#$%$%%%. When the phone rings and I say hello and there is either dead silence or someone asks who it is speaking I know it is not a friend - so I just say "wait a minute" and put the phone on a table nearby without ending the call... This wastes their time and now I get NO COLD CALLS! from about 3 an evening every day of the week and at weekends!! Of course after about 5 minutes it is a good idea to remember to press the button to end the call. If I want to change an account, buy something or make a donation etc., I will initiate the call . I sure will not act on any cold calls.