The vector t 1 m  of N age-specific mortality rates in year t+1 is modeled to be dependent on the vector t m in the present year t and l-1 other vectors before year t via a conditional distribution which is derived from an N(l+1)-dimensional power-normal distribution. The marginal distribution of the mortality rate at age x is computed from the conditional distribution. The prediction interval with end points given by the 100(α/2) and 100(1-α/2) percentage points of the marginal distribution is used to predict the mortality rate at age x in year t+1. The similar idea is used to find a prediction interval for the mortality rate at age x in year t+d where d >1. The United States mortality data from 1933 to 2000 are used to estimate the N(l+1)-dimensional power-normal distribution. The prediction intervals based on the distributions when N=19, l=1 and 2 are found to have good ability of covering the observed future mortality rates in the years from 2001 to 2010. The length of the prediction interval may be shortened by choosing small values of N and using more recent historical data. Mathematics Subject Classification: 62M10, 62P05

This Working Paper should not be reported as representing the views of the IMF. The views expressed in this Working Paper are those of the author(s) and do not necessarily represent those of the IMF or IMF policy. Working Papers describe research in progress by the author(s) and are published to elicit comments and to further debate.Myanmar's multiple exchange rate system creates various economic distortions. This paper describes the exchange rate practices in Myanmar, develops a model of foreign exchange markets, and presents the efficiency costs imposed by quasi-fiscal operation under the current exchange rate regime. The results of our model-based analyses indicate that the equilibrium exchange rate under the unified market could be at around K 400-500 per U.S. dollar, and using the equilibrium exchange rate (instead of the official exchange rate) as the accounting rate increases trade openness to more than 20 percent from less than 1 percent measured by official statistics. The total efficiency loss caused by the current multiple exchange rate regime is estimated at about

IMF Working Papers describe research in progress by the author(s) and are published to elicit comments and to encourage debate. The views expressed in IMF Working Papers are those of the author(s) and do not necessarily represent the views of the IMF, its Executive Board, or IMF management.

As medical care delivery systems grow in complexity, the understanding of interaction between entities within the system becomes a key aspect in resource planning. The model presented in this paper is geared to aiding resource planning both at the community or regional level and at the medical facility level. At the regional level the problem is related to the elimination of duplication and the sharing of services. At the medical facility level the concern is the balancing of the supply and demand of services among the departments. The framework of the model is a directed graph with nodes representing the service entities and branches representing the interrelationships. At the regional level, entities are hospitals, clinics, and centralized supportive units, such as the data center or the central laboratory. At the medical center level, entities are generally departments within the facility. An iterative procedure is used to simulate the propagation effect of a change on all entities. The model at the medical center level, as implemented in a minicomputer system was applied to a real problem. The results strongly correlated with another, independent study.

This paper discusses the evolution of the household debt in Australia and finds that while higher-income and higher-wealth households tend to have higher debt, lower-income households may become more vulnerable to rising debt service over time. Then, the paper analyzes the impact of a monetary policy shock on households' current consumption and durable expenditures depending on the level of household debt. The results corroborate other work that households' response to monetary policy shocks depends on their debt and income levels. In particular, households with higher debt tend to reduce their current consumption and durable expenditures more than other households in response to a contractionary monetary policy shocks. However, households with low debt may not respond to monetary policy shocks, as they hold more interest-earning assets.