My experience with Bonus Bonds makes me suspicious that the probability of winning is not just by pure chance.
Initially, I put a couple of thousand in and I seem to win something every other month (prizes between $20-$80). I then kept putting more in and kept getting prizes.
Fore many years I had about $8000 with BB and added no further amounts. What I noticed was that I got very few prizes when I was not adding extra funds.
Now I win $20 about every six months. Is it rigged to reward new investors so that they add more funds? It would not surprise me.
My track record of winnings set against my investment record seems very improbable. Perhaps they have an algorithm that rewards new and continuing investors?
Has the Commerce Commission ever investigated them? Perhaps they should.
It would be very interesting to see the prize and investment history of a large subset of BB investors to see whether there is any statistical pattern. I suspect there might be.