Absolutely worth reading @ajewa
Based on my knowledge, over 90% of start-ups fail within less than 2 years. So those businesses who can reach 5 year lifespan are already ... well, doing better than most :)
You're right, that either it's 95%, 65% / 5 years or 2 years - that's still a huge problem.
My personal impression is that most new businesses fail because those who are behind them have very little idea about budgeting and planning expenses. That soon ends up with their businesses struggling with lack of liquidity and money flow being disturbed.
Definetly doing research is also a must. Generally speaking - solid read.
Cheers
Piotr