This paper documents trends over the last two decades in retirement behavior and retirement income choices of participants in TIAA, a large and mature defined contribution plan. From 2000 and 2018, the average age at which TIAA participants stopped contributing to their accounts, which is a lower bound on their retirement age, rose by 1.2 years for female and 2.0 years for male participants. There is considerable variation in the elapsed time between the time of the last contribution to and the first income draw from plan accounts. Only 40% of participants take an initial income payment within 48 months of their last contribution. Later retirement and lags between retirement and the first retirement income payout led to a growing fraction of participants reaching the required minimum distribution (RMD) age before starting income draws. Between 2000 and 2018, the fraction of first-time income recipients who took no income until their RMD rose from 10% to 52%, while the fraction of these recipients who selected a life-contingent annuitized payout stream declined from 61% to 18%. Among those who began receiving income before age 70, annuitization rates were significantly higher than among those who did so at older ages. Aggregating across all income-receiving beneficiaries at TIAA, not just new income recipients, the proportion with a life annuity as part of their payout strategy fell from 52% in 2008 to 31% in 2018. By comparison, the proportion of all income recipients taking an RMD payment rose from 16% to 29%. About one-fifth of retirees received more than one type of income; the most common pairing was an RMD and a life annuity. In the later years of our sample, the RMD was becoming the de facto default distribution option for newly retired TIAA participants.

A whole-farm simulation model is used to analyze the impacts of PST adoption on representative farms in Missouri and Indiana. Farmers who do not adopt experience lower average annual net cash farm incomes than adopters. Lower feed prices and/or an average PST/feed response decrease the incentive to adopt. Payment of a 5 percent carcass merit premium (CMP) and/or higher grain prices greatly increase the economic incentive to adopt.

Managers of business firms, large or small, farm or nonfarm, must make investment decisions under conditions of risk and uncertainty. However, in evaluating investments, the assumption of perfect knowledge has often been used to simplify the analysis. For example, an estimate of average annual net returns is frequently discounted into perpetuity to evaluate a real estate investment alternative. Capital budgeting literature suggests a number of approaches to evaluating alternative investments. However, use of concepts such as the payback period, average rate of return, internal rate of return and net present value embodies the assumption of perfect knowledge.

This paper investigates the farm-level impacts of the 1996 farm bill on the South. Focus group perceptions of risk sources, observed acreage changes, and the farm-level impact of increased price risk are evaluated. Focus group respondents ranked price and yield as the two most important sources of risk, and diversification was ranked highly as a risk-management tool. Limited data suggest that acreage shifts among crops are occurring in the South, presumably aided by the 1996 farm bill. Higher probabilities of cash flow deficits are estimated for cotton and rice relative to feedgrain, wheat, and oilseed operations.

The treefrog Eleutherodactylus coqui is a direct developer — it has no tadpole stage. The limb buds develop earlier than in metamorphosing species (indirect developers, such as Xenopus laevis). Previous molecular studies suggest that at least some mechanisms of limb development in E. coqui are similar to those of other vertebrates and we wished to see how limb morphogenesis in this species compares with that in other vertebrates. We found that the hind limb buds are larger and more advanced than the forelimbs at all stages examined, thus differing from the typical amniote pattern. The limb buds were also small compared to those in the chick. Scanning and transmission electron microscopy showed that although the apical ectoderm is thickened, there was no apical ectodermal ridge (AER). In addition, the limb buds lacked the dorsoventral flattening seen in many amniotes. These findings could suggest a mechanical function for the AER in maintaining dorsoventral flattening, although not all data are consistent with this view. Removal of distal ectoderm from E. coqui hindlimb buds does not stop outgrowth, although it does produce anterior defects in the skeletal pattern. The defects are less severe when the excisions are performed earlier. These results contrast with the chick, in which AER excision leads to loss of distal structures. We suggest that an AER was present in the common ancestor of anurans and amniotes and has been lost in at least some direct developers including E. coqui.

Tetanus, one of the oldest diseases known to man, continues to exact a tremendous toll worldwide. While the incidence of tetanus has declined dramatically in the United States in this century, more than 50 cases are reported to the Centers for Disease Control and Prevention (CDC) each year. Two thirds of these cases are elderly patients. Some estimate that the actual number of cases may be two to four times greater than the number reported. The overall reported case fatality rate is about 20% to 30%, but is greater than 50% for those older than 60 years.