I don't know the percentage, but I would say the majority of the time I try to be.. The thing is, no one is perfect, there are no 100 %ers.. what I do when I mess up, is admit to it, apologize for it, explain to my kids what I did wrong, and let them know how I'm going to keep it from happening again. This is the key to good parenting. We are human. How would anyone learn to work through adversity if everything was perfect?
Good is a relative term, so what you mean by good isn't necessarily what someone else considers to be good. On the whole, I don't think anyone can be a good example 100% of the time, but I always try to be.