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10.5 Economic viability

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10.5. 1 Overview

Tools for economic analysis are probably the least known on FSD teams, which is why some time is spent in this section outlining some of the main tools. Many other references also deal with the topics in much more detail.

Most limited-resource farming households produce a mix of products for household use and sometimes for selling, Livestock (i.e., cattle or small stock) may be sold whereas basic grain production is, if not subsistence production, is at least substitution production. There are many methods for analysing potential improved technologies in a formal manner from an economic viewpoint. Three critical issues underlying the legitimacy of many of the results of such analysis are:

As indicated earlier, techniques for economic analysis in FSD continue to be relatively simple. This is so because the relatively simple techniques are most readily understood by planners and non-economists, and because field data often are not sufficiently accurate to support complex analytical techniques. This latter reason is particularly significant where the price for most of the inputs and commodities is not determined in a market. Generally, economic analysis is carried out on the 'old' as well as the 'new, technology, in order to compare the technologies and to identify changes in the whole farm system caused by changing one part of the system.

The majority of economic analyses with reference to on-farm trial work in FSD fit in three categories:

Another type of economic analysis that is highly desirable is marginal analysis. Average returns and budget analysis are based on average data values acquired from a number of replications of a trial, all of which use about the same level of variable inputs. Thus, comparisons are being made between technologies based on a given level of inputs. Marginal analysis goes beyond the comparison of a given level of inputs and looks at profitability as levels of variable inputs change, This addition allows determinations as to the best (i.e., most efficient and profitable) allocation of resources for a given enterprise, Unfortunately, marginal analysis requires data over a wide range of inputs, something that is not available in much FSD work, so marginal analysis techniques, although valuable, have not been used widely, In practice, types of data required for marginal analysis are likely to be available only from RMRI type trials, which are not a major preoccupation of FSD work.

Therefore, the type of data available will influence the type of economic analysis that is possible. In the following sections, three major types of economic analyses commonly used are described briefly, namely average returns above variable costs (i.e., gross margin) analysis, partial budgeting and sensitivity analysis, and simplified risk analysis,

10.5.2 Gross Margin Analysis

An analysis of the average (i.e., mean) costs/benefits from different technologies being examined in a trial often is made, Where all of the relevant data have been collected, this type of analysis can be used, However, this requires valuation of both fixed and variable inputs, In many cases, the variable inputs are what need to be examined, because the fixed inputs are constant for all plots in the trial, Thus, the most common analysis performed involves the average returns above variable costs (RAVC) or gross margin approach. This allows a comparison between various technologies being tested based on the inputs the farmer must provide.

The procedure for gross margin analysis is:

This analysis generally is done on a per hectare basis, and the return calculated is a return to management, assuming that land is fixed and that labour has been valued at the price of its best alternative use (i.e., opportunity cost).

In order to maximize profits, it is necessary to maximize returns to the most limiting resource. For example, land may not be the most limiting resource, The most limiting resource may be traction time or labour for ploughing or weeding. When the most limiting resource is known, it is possible to calculate an average net return to that resource for the different technologies being compared and choose the most favourable technology. This procedure will not maximize the returns, because it does not examine different levels of inputs, but it will maximize the returns to the most limiting factor for a fixed level of inputs. For example, it is possible to calculate a return to weeding labour by omitting weeding labour costs (i.e., all other labour costs are included) from the cost total and then dividing the return by the number of hours of weeding labour, giving a return per hour of weeding labour.

10.5.3 Partial Budgeting

The partial budget is a way of analysing differences in costs and benefits of two or more competing enterprises or technologies. A good start for any economic analysis of a technology, including budgeting exercises, is to make a statement of the farmers' objectives, especially as they relate to the particular farm enterprise/technology.

The second step in any budgeting exercise is to make a detailed description of the technology or enterprise. For partial budgeting, it is necessary to be concerned only with those things that change from the existing technology to the proposed one. For budgeting in general, this step includes:

Partial budgeting is a method of organizing data and information about the costs and benefits from some change in the technologies being used on the farm. Thus, partial budgets are useful tools for analysing small changes in farming systems and require less information than a whole farm budget or an enterprise budget, They measure changes in income and returns to limited resources; provide a limited assessment of risk; and, through sensitivity analysis, suggest a range of prices or costs at which a technology becomes profitable,

Partial budgets are not used to estimate the total income and costs for each of the technologies being considered. The goal is to estimate the difference in benefits or losses expected from the technologies. The partial budget technique is most useful where the new technology consists of the existing technology with one or two changes. The following steps are used in creating a partial budget:

To interpret this partial budget (Table 10.3), note that the increase in benefits more than makes up for the reductions in benefits, Even though more costs are associated with the new technology, there is a net gain of almost P20 per hectare from using the new technology (i.e., double ploughing) over the traditional (i.e., single ploughing) technology. In its most simple interpretation, it does pay to switch from single ploughing to double ploughing in conditions similar to those where the tests took place. The change (i.e., increase) in benefits was larger than the change (i.e., increase) in costs necessary to produce that benefit.

It is also possible to look at changes that are likely to occur if prices, yields, or input requirements change. In other words, it is possible to investigate how sensitive the results are likely to be to such changes -- a primitive measure of risk. This is done easily by setting the partial budget up on a spreadsheet such as Lotus 123. Table 10.3 shows the results that will occur if the value of labour increased or decreased by 50 percent, and what the wage rate would need to be if no increase occurred in net return from double ploughing compared with single ploughing.

TABLE 10.2: PARTIAL BUDGETING FORMAT

1. Additional benefits: List the items of income from the new technology that will not be received from the existing technology.
2. Reduced costs: List the items of expense for the existing technology that will be avoided with the new technology.
3. Subtotal increases Add lines 1 and 2.
4. Reduced benefits: List the items of income from the existing technology that will not be received from the new technology.
5. Additional costs: List the items of expense from the new technology that are not required with the existing technology.
6. Subtotal decreases: Add lines 4 and 5,
7. Difference A positive (negative) difference indicates that the net benefits the existing technology by the amount shown of the new technology exceed (are less than) the net benefits of.

Source: Based on Boehlje and Eidman [1984: p. 237]

A partial budget is easy to interpret. However, it rarely is presented with a statement of the farmer's objectives, the farmer's resource base, and important non-cash considerations. A first consideration should be the question: does the criterion of increasing net benefit per hectare imply that it is in the farmer's interest to maximize returns to land? Often, this is not the case. The partial budget does not indicate if the draught and labour are available to the farmer to do a second ploughing, or if the farmer has the capital to hire a second ploughing, if ploughing is done through a hire arrangement. For many farmers, the availability of labour or capital may be more constraining than the availability of land. As has been repeatedly emphasized, the evaluation criterion used should maximize returns to the most constraining variable.

Although it a useful technique, there are limits to its value. Three problems that partial budgets do not address directly are:

TABLE 10.3: PARTIAL BUDGET: DOUBLE PLOUGHING INSTEAD OF SINGLE PLOUGHING A SINGLE HECTARE, MAHALAPYE AND FRANCISTOWN AREAS, BOTSWANA, 1983-87

ITEM PULA PULA
REDUCED COST (in Pula)    

Weeding time saved (6,2 hrs @ P0.38/hr)

2.36  

Single-plough harvesting time (25 hrs @ P0.38/hr)

9.50  
ADDED BENEFITS    

Double-plough yield (197 kgs @ P0.43/kg)

84.71  

SUB TOTAL INCREASES

  96.57
ADDED COST    

Double-plough second ploughing (29.7 hrs @ P).38/hr)

11.29  

Depreciation on equipment

1.50  

Double-plough harvesting time (43.8 hrs @ P0.38/hr)

16.64  
REDUCED BENEFITS    

Single-plough yield (111 kgs @ P0.43/kg)

47.73  

SUB TOTAL DECREASES

  77.16
NET GAIN   19.41
SENSITIVITY ANALYSIS    
Net gain when:    

Value of labour @ P0.57/hr

  11.37

Value of labour @ P0.19/hr

  27.44

Value of labour @ P0.84/hr

  0.00

Source: Worman [1987]. Tables 10.4 to 10.6 are also derived from the same source.

10.5.4 Risk Analysis

Unfortunately, not all inputs are under the farmer's control. In Botswana, one of the most critical inputs for rainfed agriculture is soil moisture. There is a great deal of variability in rainfall between years, within years, and even between plots in the same village. This highly variable rainfall introduces a great deal of risk and/or uncertainty into the farming system. There may be other sources of risk as well, such as uncertainty about the availability of seed or traction. Farmers consider risk in their farming system and make adjustments to compensate. In Botswana, one of the traditional methods of addressing risk is to plant a large number of plots over a period of time in order to take advantage of the rains that do come. Another risk-reducing mechanism is to keep the investment of labour and cash in arable agriculture as low as possible. Thus, the farmer will not weed a plot if he/she thinks that plot will fail.

By looking at the distribution (i.e., range) of returns from experiments, it is possible to obtain some information on how risky a particular technology may be. There are several simple tools for looking at the distribution of returns, which can help in examining the question of risk. A very primitive method was indicated in the preceding section. It was shown that partial budgets also can be used to assess risk when a sensitivity analysis is included to show expected net gains from changes in levels of certain variable inputs/outputs and/or their prices (see Table 10.3).

In the real world, no two farmers have the same attitude toward risk. Some are more inclined to take risky actions (e.g., before, during, or after the cropping season) with the ultimate hope of receiving a larger return on their investment of labour and cash. Some are less inclined to do so. When one interprets farmers' risk attitudes, it is important to assume that they realize a trade-off may exist between getting a greater return from a technology and assuring stability in the return (i.e., that there are few years with little or no return).

Farmers generally are grouped into three categories in relation to their attitudes toward risk.

Farmers may fall into different groups depending on the season, the amount of resources available at that particular time, the magnitude of the cost, and the potential gains and losses from a given technology. When FSD workers interpret risk for technologies, it is important to remember that farmers will look at risk differently and so may fall into different recommendation domains based on their attitude towards the risk involved in a particular technology. However, in general, particularly with reference to major enterprises, limited- resource farmers in low income countries are likely to have a risk-averse attitude.

Generally, a farmer will have some idea of the risk of crop failure under the cropping system he/she currently uses. When considering a shift to a different cropping system, the farmer usually thinks not only of the cost of additional inputs (i.e., labour and cash) and the potential net gain in returns (i.e., whether considered in terms of yield or cash value), but also the increased or decreased risk of having a crop failure. If farmers think that risk will be increased under a new technology, they often will want to see a larger net gain from the shift to compensate for the increased risk. An increase in yield or net returns of 30 percent over the existing technology is probably the minimum increase that most farmers will consider acceptable before they adopt the technology. The opposite is also true. A perceived decrease in risk will often induce farmers to shift technologies, even if the gains from doing so are small.

Actual measurement of farmers' risk attitudes is very complex and not practical, because the attitudes are always changing, Thus, methods for estimating risk are based on the actual data collected in trial work, rather than trying to measure farmers' attitudes toward risk,

Two simple ways of analysing risk that depend on the outcomes from trials comparing new technologies to existing technologies are as follows:

Strictly speaking, a safety-first analysis is the probability (i.e., percentage of the time) that a technology exceeds a specified output level. Two or more technologies can be compared, and the one that produces at least the desired output level the highest percentage of the time is preferred. A second way of looking at the same issue is to determine the percentage of the time that a technology falls below a specific minimum level that must be reached. Table 10.4 provides some data on the percentage of times that some factors, considered in singleploughing and double-ploughing trials, were above the specified minimum. It appears that double ploughing was generally better in this measure of risk than single ploughing.

One way to provide more information to the farmer is to compare the median, which is the value that is half way between the highest and the lowest value, with the mean. If the median is less than the mean, it indicates that the farmer will receive less than the mean return more than half of the time. It may be helpful to look at how much difference there is between the mean and the median. If there is little difference, then the farmer will receive close to the mean most of the time. A lot of difference may indicate a few really good returns for the technology and many rather poor ones. Actually graphing the distribution can help in determining what is happening in the relation of means and medians. These are some indications of the skewness of a distribution.

Another potentially useful measure is the percentage of the time that a farmer can expect to receive a yield or return less than the mean yield or return. If this percentage is high, it generally indicates a situation of a few good and many poor yields or returns. Table 10.4 provides information on the mean, median, and percentage of times the yield or return was less for some single-ploughing and double-ploughing data. Although, in general, both the mean and the median were greater for the double ploughing, indicating a possible overall advantage, the percentage of the time that single ploughing was less than the mean was smaller than for double ploughing, indicating that double ploughing may be somewhat less stable.

FSD workers may want to consider using an average of the five lowest yields rather than just the lowest yield for comparison purposes. In the case of the data from Table 1().4, the lowest yield for both single ploughing and double ploughing was zero (i.e., no yield). This produced net losses of P2.70 for single ploughing and P5.70 for double ploughing. Comparing an average of the five lowest yields gave average of 1.8 kilograms/hectare for single ploughing (i.e., average return of minus P 1 .97), whereas the five lowest yields for the double ploughing averaged 19.4 kilograms/hectare (i.e., average return of P2.90). This implies, that all other things being equal, farmers may prefer the double-ploughing technology. This method is sometimes called minimum returns analysis [CIMMYT, 1988A].

TABLE 10.4: SOME INDICATORS OF RISK, RMFI DOUBLE-PLOUGHING TRIALS, FRANCISTOWN, BOTSWANA' 1985-87

VARIABLE N MEAN MEDIAN % < MEAN % > MINIMUM
Yield kg/ha:         70 kg/ha

Single plough

20 110 88 60 65

Double plough

20 228 191 70 75
Net return to total labour (P/hr):         P 0.38/hr

Single plough

20 0.47 0,42 55 55

Double plough

20 0.57 0.40 60 65
Net return to traction hours (P/hr):         P 0.38/hr

Single plough

20 1.64 1,07 60 50

Double plough

20 2.12 1.15 75 65

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