For the staticians amongst you. After a severe heart attack aged 45 I was given a less than 50% chance of surviving 5 years. Since then various and different consultants have put the odds of surviving each successive 5 year period at less than 50% for the last 25 years. Should I be encouraged that since I am still here I will continue to beat the odds until old age finally gets me? Or should I regard myself as having long entered negative survival territory and be lucky to finish this sentence .....?