What does the future hold? This is a question we all would like to know the answer to, which may help explain why business is good for Tarot card and palm readers. Our interest in the future has also been good for meteorologists, who get some prime-time news to tell us what will happen tomorrow, and for political scientists and pollsters who appear every two years to forecast election results. The widespread interest in seeing into the future was a theme picked up by John Casti, in his 1990 book Searching for Certainty: What Scientists Can Know About the Future. Casti looked at a wide array of forecasts by researchers / scientists in a number of fields and attempted to evaluate their forecasts. At the head of the class were Quantum mechanics and Celestial mechanics where the forecasters received an A. Those specializing in forecasting the stock market found themselves in the middle of the pack with a grade of C+, slightly better than the C- received by those in the business of forecasting war.
All of these forecasters, however, received better grades than the economists who got a D for their efforts, which put them slightly ahead of the D- given to Evolutionary biologists. Maybe it is not surprising that economic forecasters fared so poorly. If you look at the economic press in the mid 1990s you will find stories predicting the Asian century and trumpeting the Asian secrets to growth, and very little advance warning for the economic crashes of the late 1990s. And then there was Professor Franklin Fisher's opinion that stock prices had reached "what looks like a permanently high plateau," which he offered just prior to the stock market crash of 1929 that ushered in the Great Depression.
To understand the grade, it is essential that we understand what it is that economists are getting graded on. In this unit we will be looking at economic forecasts. More specifically we will be looking at the three interrelated questions: When in the future are they forecasting? What are economists forecasting? and How do they develop their forecasts?
When in the future?Let's start with the, When in the future question. If you return to the work of the earliest economists you will find that any forecasts they made dealt with the long-term - what will happen in twenty, fifty, or one hundred years, not what will happen in the next month or quarter. Adam Smith, taking the very long view, saw the market system as providing the world with something new - economic growth. This growth was not something that would happen in the near future, and it was not something that would be forecast with much degree of accuracy, but it was certainly a forecast. And it was an optimistic one at that. Following up on this long-term theme, Thomas Malthus came away with a decidedly more pessimistic view when he peered into the future. What Malthus saw was a world where the geometric growth of population would quickly outstrip the arithmetic growth of food. The result was the world's people would always be condemned to live at a subsistence level. The pessimism implicit in this forecast was not lost on others and it was this forecast that got Economics dubbed "The Dismal Science."
There is still interest in the long view. One example would be Peter Schwartz, who in the Art of the Long View, pushes scenario planning where a forecaster sets out to identify the drivers, the agents of change that "influence the outcome of events." Schwartz compares developing a forecast to solving a murder mystery. Once you know the motives, you are well on your way to solving a murder mystery, and once you have identified the drivers, you are well on your way to developing a forecast. One of the examples he mentions is the ancient temple priests' forecasts of the Nile River.
"Every spring, the temple priests gathered at the river's edge to check the color of the water. If it were clear, the White Nile, which flowed from Lake Victoria through the Sudanese swamps, would dominate the flow. The flooding would be mild, and late; farmers would produce a minimum crop. If the stream appeared dark, the stronger waters of the Blue Nile, which joined the White Nile at Khartoum, would prevail. The flood would rise enough to saturate the fields and provide a bountiful harvest. Finally, if the stream showed dominance by the green-brown waters of the Aterba, which rushed down from the Ethiopian highlands, then the floods would be early and catastrophically high. The crops might drown; indeed, the Pharaoh might have to use his grain stores as reserves.
The driver behind the flooding of the Nile was the relative strength of the three rivers, and with information on this the priests had their flooding forecast. A second example offered by Schwartz is the work of Pierre Wack for Royal/Dutch Shell in the late 1960s and early 1970s. Wack observed the increasing dependence of the US on imported oil, the growth in oil demand, and the resentment toward the West of OPEC countries due to the Arab-Israeli war of 1967. Wack concluded these forces could very well lead to rather dramatic oil price increases and Shell should plan accordingly. By 1973 the scenario was playing itself out as the OPEC countries cut off the supply of oil to the west and the price rose dramatically.
Where does one look for the 'drivers'? Schwartz identifies five factors: Society, Technology, Economics, Politics, and Environment. Hamish McRae, in his book The World in 2020, identifies two drivers - demographics and technology. One example which highlights the importance of demographics, and one you should be familiar with, would be the forecasts of the future of social security. We have all heard of the dire forecasts of difficulties encountered when the baby boomers begin to retire. It is fairly easy to see that many factors will have an impact on the retirement decision - health, income, wealth, occupation, and marital status at any time - but that the real driver is age, and the number of retirees will be dependent upon the number of people over age 65. In the graph below it is very obvious that in the decade ending in 2020, the real 'crisis' will emerge as the boomers begin to hit age 65. In that decade the number of people aged 65 or older will increase nearly 80 percent (solid blue columns) while the working age population will actually decline (maroon-lined columns). Similar analysis is behind the explanations for the decline in crimes experienced in American cities in the late 1990s. Crime is down simply because there are fewer teenagers who are in the high crime rate age bracket.

Technology is also a prime driver and history is filled with examples of where technology altered the pattern of growth. The adaptation of the steam engine to textile mills moved the center of the textile industry from Lowell, MA to Fall River, MA; the automobile was behind the suburbanization of the US population; and air conditioning contributed to the explosive growth of the Southwest. In 1998 one of the favorite topics is the impact the internet will have on various industries ranging from banking to retail shopping to education.
By the 1960s we were seeing the early stages of a movement toward short-term forecasting. This movement could be attributed to four factors - the theory, the numbers, the machine, and the market. The theoretical basis for concern with the short-run was provided by John Maynard Keynes. In the 1930s, when Keynes published his General Theory, the world was suffering through the Great Depression and there was a sense of immediacy to addressing the problems of falling output and employment. As we saw in our discussion of the 1930s, Keynes worked hard to direct the profession's attention toward the short-run and away from the long-run. More importantly, Keynes' theory offered the basis for government intervention as his "multiplier" replaced "crowding-out" in discussions of macroeconomic policies.
And then there were the data the US government had begun to collect and publish after W.W.II - the numbers needed for the short-term forecasting. During the Great Depression there were very few statistics available to monitor the economy's performance - none of the wide array of statistics that you hear in the news today. To remedy this situation, Simon Kuznets was given the task of leading the effort to construct the national income accounts for the US. The direct result was the GNP statistics published by the Commerce Department, but certainly there was a spin-off as other government agencies began to collect and publish various measures of the macro economy and its four primary markets (output, labor, capital, and foreign exchange). By the mid 1960s, adequate macroeconomic data existed that provided economists with the basis for constructing the statistical models that would bring realism to the theoretical work of Keynes.
For example, Keynes talked about the marginal propensity to consume (MPC) and highlighted the importance of this link between consumption and income in explaining the government multiplier (the change in income (DY) generated by a change in government spending (DG). The formula in the simplest Keynesian macroeconomic model for the government multiplier was: DY/DG = 1/(1-MPC). For this model to provide a useful forecast of the direction of change in income, or the effect of government spending on income, we would need to know the value of the multiplier. This, in turn, meant we would need to know the value of the MPC. One way to establish the value of the MPC would be to look at the data on income and consumption and 'test' for the nature of the relationship, and by the mid 1960s the data sets existed.
The testing of the theories brings us to the third factor - the machine. By the late 1960s and early 1970s early versions of the computer were making possible the statistical analysis needed to test these theories.
But was there a market for these forecasts? John Kenneth Galbraith, in his books The New Industrial State and The Affluent Society noted that the rise of the mega corporation raised the level of investment spending which generated demand for forecasts to avoid potentially expensive mistakes. And the government provided a strong demand for forecasts to provide the basis for macro policies. The Keynesian revolution had created a generation of economists and policy officials who believed the economy could be controlled, the business cycle that had plagued capitalist economies could be defeated. These were heady times for economists as there was a widespread belief that the secrets of the economy could be discovered. All that was needed was a model of the macroeconomy, the same model that others would use to forecast the performance of the economy. Now we can briefly look at the second question.What do economists forecast?
The primary focus of economists' forecasting efforts have been on the performance of the aggregate markets - the quantity and price measures of the output, labor, capital, and foreign exchange market. It is highly unlikely you will get through a week of reading the financial press without running across some economic forecasts of macro aggregates such as interest rates, inflation, GDP, unemployment, and the exchange rate.
The reason is there is a widespread belief these numbers matter. The numbers certainly matter to politicians since rising unemployment rates or slowing growth are often leading indicators of election day troubles for incumbents. Richard Nixon, who lost in 1960 to John F. Kennedy, and George Bush, who lost in 1992 to Bill Clinton, can attest to the impact of the economy's performance on their election losses. In 1998, the unthinkable happened in Indonesia as Suharto, the nation's long-time ruler, was "eased" out of power. He was only the most notable casualty of the Asian economic crises in 1997-98. And in 1999, Bill Clinton was able to manage high levels of popular support during the impeachment hearings - a testament to the booming US economy that had managed to remain an "island of prosperity" in a sea of deepening world recession.
Businesses also care about the performance of the macro economy since their "bottom line" can be very much influenced by the economy's ups and downs. In late 1998 Alan Greenspan, chair of the Federal Reserve (Fed), lowered interest rates in the capital market with the hopes the lower rates would spur spending in the output market. This is the reverse of what we saw in the early 1980s when Paul Volcker, chair of the Fed drove up interest rates, bringing home mortgage rates to near 20 percent range and effectively putting the brakes on the housing industry. And in 1998, the concern hanging over the industrialized world was the decline in the Asian economies would translate into lower export sales by US companies. The forecasts of lower corporate earnings based on these economic forecasts were responsible, at least in part, for the drop in the stock market.
This was the situation confronting Sam who had his market located in western RI. The accompanying graph describes the pattern of sales at Sam's market during much of the 1970's. As you can see, in 1973 Sam's suffered a substantial drop in sales and never regained the loss. Sam, the owner of this intermediate size super market was looking for an explanation for the loss. Some of the obvious candidates would be new super markets moving into the area, changes in advertising strategies, or major construction in the area that reduced customer access to the store.
Another place to look would be at the 'macro' environment. Anyone familiar with macroeconomics would tell you that 1973 marked the beginning of the OPEC induced recession that hit the New England region hard. The result was many businesses suffered losses. In the diagram below, indexes of sales of Sam are contrasted with the overall sales in the region and it is clear that Sam's troubles simply reflected the troubles in the broader, macro economy. [for a discussion of indexes see Benchmarking]. The prevalence of this type of causality from the macro economy to the individual firms and industries has created a very real demand for macroeconomic forecasts.

Another example would be forecasts of prices. Just as it would be difficult to forecast sales without some sense of the underlying strength of the economy, it would be impossible to forecast or explain prices without an understanding of the underlying inflation rate. One of the best examples would be wages - the cost of labor. If you look at the following graph to answer the question, in which decade did wages grow fastest, the obvious answer would be the 1970s. This is what students have said for years when confronted with these data.

What was driving this was not the condition in the labor market, but rather the underlying rate of inflation. Wages were rising because prices were rising. To understand the above average wage increases in the 1970s, it is essential to understand that the 1970s was also a period of above average inflation as you can see from the graph below.

The situation would be the same if you were dealing with
interest rates. If you wanted to forecast interest rates, you would need information
on inflation rates. This relationship between the inflation rate and interest rate (on
short-term government securities) is apparent in the diagram below. The 18 percent
mortgage rates that we saw in the early 1980s could not be explained without being placed
in the context of the double-digit inflation rates.

At this point we have looked at two of the questions - how far into the future, and what will we forecast. Now we will turn our attention to the how question.
How do economists forecast?To highlight the different forecasting techniques, let's look at a very simple problem - the situation at Itzibitzi motorcycles. The questions facing the company is: What will sales be over the next 5-6 years? Will these sales be adequate to justify a new production facility? In this section we will look at three techniques - time-series analysis (the Ruler), econometrics (the Relationship), and barometric forecasting (the Experts).
Itzibitzi MotorsYear |
Sales (units) |
1960 |
9073 |
1961 |
9287 |
1962 |
9853 |
1963 |
10094 |
1964 |
10500 |
1965 |
11321 |
1966 |
12216 |
1967 |
12315 |
1968 |
12970 |
1969 |
13320 |
1970 |
14038 |
1971 |
14580 |
1972 |
15057 |
1973 |
15951 |
| 1974 | 18120 |
| 1975 | |
| 1976 | |
| 1977 | |
| 1978 | |
| 1979 |
The first step is to look at the picture of these data - the time-series graph provided below. The data is the same as you find in the table, it is simply a bit easier to visualize. What is much clearer in the graph is the upward trend in sales, and the upturn (faster growth) toward the end of the period. If you return to the table you will not see this acceleration nearly as easily as you do in the graph.

Whenever we are dealing with a time-series of data, there are three possible components that you should attempt to identify - seasonal, cyclical, and secular (trend). Retail jewelry sales peak each year in December and collapse in January, while unemployment rates on Cape Cod, MA rise in the winter months and fall during the summer at the peak of the tourist season. These are seasonal variations and we can see the seasonal pattern of retail sales, restaurants, lunchrooms, and cafeterias in the diagram below. Each year sales peak during the summer months and fall toward the end of the year. If you are not interested in seasonal patterns, you will most likely want to use seasonally adjusted data which smoothes out the data. Generally you will work with seasonally adjusted data or annual data for which you do not need to worry about seasonal adjustment.
The second component is the cyclical component - the patterns of up and down that generally tend to be associated with the business cycles. These movements tend to be longer than a year, but shorter than five years. In the diagram above, the peak in 1992 is substantially lower than you would have expected based on the rest of the data. What you are seeing is the impact of a fairly severe recession which lowered sales. A somewhat better picture of the cyclical patterns in any economic data can be seen in the graph of the prime interest rate (NSA - not seasonally adjusted). During the thirty year period, prolonged interest rate rises tended to be followed by periods of declining rates - after each peak ( 1974, 1980 and 1982, 1984, 1990, and 1995) rates tended to fall and bottom out before renewing their rise.

The final component is the trend - the long-term direction in which the curve is going. In the retail sales graph, there is a very definite upward trend and some variation about the trend. In the prime rate graph, meanwhile, it looks as though there is a positive trend through the early 1980s followed by a general downward trend since then. In the dollar/mark exchange rate graph, the downward trend in the exchange rate is interrupted only by a very steep increase during the first half of the 1980s.

Now that we have looked at the decomposition of the data, let's look at the techniques for forecasting.
Time-series analysis (the ruler)
The basic assumption underlying this approach is the only information that you need to forecast the future is information on the past. It is all there, you only need to uncover it. In the diagram below you will see the red line. For those with limited math / statistics skills, you can think of this as the result of someone using a ruler to draw a curve that closely follows the trend in the data. If you have some background in stats, then you can think of this as the result of a simple regression of sales against time.

Econometric Models (the relationship)
The second approach is based on uncovering the interrelationships between the economic variables. For example, if we can explain consumption spending in terms of income, then once we have a forecast for income, we have a forecast for consumption spending. Returning to our earlier examples, if we are forecasting wages or interest rates, then we would need to base them on forecasts of the inflation rate. The basis of the projection is an equation between what you are explaining (endogenous variable) and what is explaining it (exogenous variable).
There would be two steps to the approach. The first step would be to estimate the relationship between the two variables for the historical period where you have the data. The place to start is with the "theory." In the Itzibitzi problem, you start with developing a list of what you think would explain sales of motorcycles? The relative importance of the explainers would depend upon the time horizon, but certainly one variable that would be important for a five year forecast would be the number of potential buyers. An obvious choice in the Itzibitzi problem would be to have sales (S) as the endogenous variable and the size of the population aged 16-25 (P) as the choice for the exogenous variable - more people means more sales.
We'll keep it simple and assume that it is a linear relationship of the form:
S = a + b*P
Regression analysis would be used to find estimates of the parameters (numbers) a and b so that the line generated by the regression does the BEST job of matching the actual pattern of Itzibitzi's sales. In this example the results would be:
S = -3299 + .546*P
The estimated line looks very much like the estimated line in the time-series graph because population generally grows rather steadily - just as time does. The estimated equation does a reasonable job of explaining the actual pattern of sales, but once again the acceleration in sales in the mid 1970s is not picked up in the econometric analysis - at least not with this exogenous variable. It could be there is another variable, possibly the price of gas that changed sharply in that period, which would have had an effect on motorcycle purchases.

To move from this historical explanation of past sales to a forecast of future sales, you would need to have a forecast of the population (P) and plug this into the equation. In the diagram above the red line is the forecast for sales based on the equation. The flattening of the line indicates that the growth of the population in that age bracket is slowing and that this should translate into slower growth in sales.
Another likely 'driver' for the forecast would be GDP which gives us a measure of the ability to pay - the higher the level of GDP, the higher the level of income to support the purchases of the motorcycles.
How do we relate this back to macroeconomic forecasting? As a first step, let's return to the simple Keynesian model of income determination and keep it real simple. The first equation is the aggregate supply = aggregate demand equation that gives us GDP (Y) as the sum of consumption spending (C) and government spending (G). The second equation is the Keynesian consumption function that specifies the relationship between consumption spending and GDP.
(1) Y = C + G
(2) C = 100 + .75*Y
The second equation would be estimated by using the historical data on consumption spending and GDP you could have found on-line at the Economic Report of the President web site. With a little bit of math we can combine the two equations to eliminate C and get the equation
(3) Y = [1/(1-.75)]*G
Now we are ready to forecast. Once we have the equation, all we need is a forecast of government spending (G) and we will have a forecast of GDP. In a more realistic model, we would include investment spending and an equation that explains the level of investment spending. Given our discussion of investment spending, it is likely that interest rates would be a determinant of spending. Interest rates, however, are influenced by the decisions of the Federal Reserve, and thus in a more complete model you would find the decisions of the Fed and the government be drivers of the macro forecasting models. Another driver would be the state of the international economy - something you heard much about in 1998 as the Asian crises was reflected in forecasts of slower growth or even recession.
Barometric forecasts (the experts)
The third approach to forecasting would be to turn to the experts for their opinions - a decision that would lead you in two directions. One possibility would be the consensus forecasts, such as the Blue Chip Indicators, that provides forecasts on an array of macro variables based on surveys of economic forecasters. The second possibility would be to look at the indexes of leading indicators. The idea here is quite straightforward and is demonstrated in the diagram below. It would be wonderful if when we were interested in forecasting a variable (blue line), we had information on some other variable (red line) that followed a similar pattern, but simply did it a bit earlier. In the diagram below, you can see a very good leading indicator, one that allows us to forecast what will happen four years in the future. For example, if we knew the leading indicator reached a turning point at A, then we would be able to forecast at B there would also be a turning point.

Unfortunately, the indicators that exist are not this good. The Conference Board, a private sector organization, took over the job once held by the US Department of Commerce and now publishes the Index of Leading Indicators. A few of the variables that are included in the index are building permits, the money supply, and change in manufacturers unfilled orders, durable goods. The idea is these variables give us advance warning of impending changes in the economy. For example, building permits would give us an indicator of what levels of construction activity would be expected in the next few months, while a faster growth in the money supply could be expected to work its way into the economy where it would eventually lead to growth in demand.
How have these forecasts done? There is no simple measure of success, but what we can be certain of is that the optimism that surrounded economic forecasting in the 1960s and 1970s has all but disappeared. The confidence that economic theory had provided policy makers with the means to make sound policies and eliminate the business cycle proved to be unfounded in the recession of 1973. The same could be said about economic forecasting. The promise that better data and better statistical techniques would allow us to refine the forecasting models to provide ever more accurate forecasts was never delivered on. We are now ready to move into the 1970s to explore in detail the events that ended our hopes of uninterrupted and predictable growth.