Retirement funding can be a trickypuzzle to piece together for the averagephysician-investor. When is it time to beaggressive vs conservative and what's thebest allocation? The lifecycle fund, alsoknown as a target-date or maturity fund,is a helpful investment strategy alternativethat has been gaining in popularity, theirassets jumping more than 65% in 2004.Investors choose them based on a projectedretirement year. A professionalmanager takes it from there, graduallyswapping investments to balance risk toleranceas the years go by. Just be sureyou're not paying exorbitant fees. Stickwith fund firms like Vanguard and T.Rowe Price that charge only the underlyingfunds'expense ratios or a small additionalamount. Each fund has a one-size-fits-all mentality; make sure yours fitsyou. Also, don't invest in several otherfunds on top of a lifecycle fund; this willundercut its key advantage (simplicity)and throw off your allocation.