Many retirement savers have not put away enough assets to support what they expect to need in the future, according to a recent survey. Only 41% of respondents said they have tried to calculate how much savings they will need. About one-third said they expect to retire before 65 and would take reduced Social Security benefits. The poll included nearly 1,000 individuals between the ages of 40 and 73 who were working part- or full-time. Overall, 74% were saving for retirement.