How often do post series A startups fail?

The question is pretty self explanatory. A friend of mine said that 1% equity at a post series A startup is "virtually the same as $1M in salary". If that's true, it means there is almost no risk in taking equity at a (well funded) startup relative to an established company. I'd like to know if this is true, because it'd be amazing if it was - it would mean that investors rarely make mistakes with this type of investment.

My few minutes of Googling didn't turn up any hard numbers. Anecdotes are nice but I would love to actually see some stats if anyone knows. Can I hear your stories and your data?