Description: This is the abstract of a paper that presents a Bayesian model for analyzing time-dependent data. The model allows for the possibility of a shift in the level and/or a shift in the variance of the process at all time points. An example of simulated data will be shown as well as the results of four macroeconomic time series data: inflation, interest, unemployment, and wage. The fitted data of the model is compared against the actual through the use of prediction intervals and the creation of a new measure, called the 'modified Akaike Information Criterion'.