This is an example of macroeconomic modeling. This economist is looking at past trends and in growth, unemployment, and inflation. Based on prior trends, some macroeconomists make predictions about future changes in growth, inflation, and unemployment. An economist can use this data as a variable to create a formula that using prior data can give a range of outcomes for the next quarter or year of data. While many in the media look to economists to tell them what exactly is going to happen in the near future, many serious economists resist making such predictions. As in many other social sciences, many predictions are wrong based on the unpredictability of key factors such as weather, human behavior, and natural disasters.