Vanguard warns that too conservative a retirement portfolio holding very few equities may present long term risks in view of increasing longevity. Also suggests consideration of annuities at some point. Perhaps 30 years of retirement funds, the usual financial portfolio planning scenario, will not always be sufficient for our future needs. We seem stuck in a time period when future investment returns appear to be lower than historical averages and yet with longer lifespans, our needs appear to be greater. Not exactly a happy New Year's message but perhaps one we need to consider seriously.According to one study by the Society of Actuaries, there is roughly a 50% chance at least one partner of a male/female couple who are age 65 today will be alive at age 93. For unmarried individuals, a 65-year-old man has a better-than-50% chance of living to age 86, and a 65-year-old woman has a roughly 50% chance of living to age 89. And actuaries expect these numbers will continue to rise.