I first invested in Zion back in 2008 or 2009. I can't find the exact date, but I traveled to Israel in 2009 and went to see the well site then and know I had a bunch of shares at that time.
This is pretty embarrassing, but in full disclosure, I bought 200 shares in November 2008 for an average share price of $6.375.
When I wasn't paying attention, and was a lot dumber, I bought more shares for almost $9.00 thinking we had a gusher...it was nothing more than the Russell 3000 Index Rebalancing. (don't judge me)