Teck Cominco has had a success rate of 1 in 243 when it comes to exploration properties and has explored or had in interest in around 6000 properties. So with Teck about 3 per 1000. Works out to about 9 or 10 properties over the past 20-30 years. I read that somewhere and I'm not sure about the time frame exactly. As for the chances of a junior making it 1 in a 1000, I've heard this number tossed around, but it may be much higher.