Some economics of zero-hours contracts – part 3: the fixed costs of working

The Unite Union, which represents about 7000 workers across New Zealand, has announced a campaign against zero-hours contracts. Zero-hours contracts have no specified hours or times of work so a worker could end up working 40 hours one week and none the next.

Unite national director Mike Treen did not know of the specific numbers of such contracts, but said these contracts were particularly common in the fast food industry, although they also appeared in some other industries.

Unite Union’s national director said that zero hours contracts made workers vulnerable to abuse as they became too nervous to speak out, for fear of having their hours reduced.

There’s no security and it puts enormous power in the hands of managers. People are extremely reluctant to assert their rights for simple things like breaks…

Treen admitted that zero-hours contracts gave employers flexibility, but pretended to know that the amount of flexibility employers actually needed was often exaggerated.

It’s not like they have huge swings or anything. They know how much they are going to sell on any particular day of the week during the year… We don’t expect everybody to have guaranteed hours but 80 per cent of the crew should be able to have it.

Treen said the union was not planning to push for a law change at this stage and would focus on addressing the issue during negotiations with fast food companies early next year.

The new leader of the opposition has promised to outlaw these zero our contracts when he gets into government. I wish him well in drafting a law that outlaws zero-hours contracts without outlawing some part-time and casual jobs as well.

 Zero-hours contracts and the class war

As is to be expected, the Guardian is rather hot and bothered about zero hours contracts. One of its columnists referred to those on zero-hours contracts as the new reserve army of the unemployed:

It is a pity Karl Marx was not around last week to comment on the news that 90% of the workers at Sports Direct are on zero-hours contracts.

The author of the Communist Manifesto would also have had plenty to say about the news that the official estimates of those working in this form of casualised labour had shot up by 25%…

It is safe to say Marx would have cavilled with those who see zero-hour contracts as an expression of Britain’s economic strength, a demonstration of flexible labour markets in action.

He would have thought "reserve army of labour" a better description of conditions in which workers were expected to be permanently on call for an employer.

The Guardian went on to admit that the reserve army of unemployed are not as discontented as they should be:

It’s only fair to say that some employees are content to be on zero-hours contracts.

Some students, for example, want to combine work with study and are willing to turn up when summoned. That’s also true of older workers topping up their pensions with a bit of irregular, part-time work.

Despite this, the class war continues as does the immiseration of the proletariat and the long-term decline in profits that will lead to the crisis in capitalism and, with a bit of luck, the inevitable proletarian revolution:

Marx would have seen zero-hours contracts as the continuation of a long historical trend, stretching back to the mid-1960s when the profitability of western manufacturing firms started to fall.

From that moment, he would say, the search was on for measures to boost profits, and this has manifested itself in a number of ways: by direct attacks on organised labour; by the increased financialisation of the economy; by the search for cheap raw materials whatever the environmental cost; and by asset bubbles.

Accordingly, zero-hours contracts are the response to tougher conditions facing firms as a result of the financial crisis.

Reversing that trend will require more than legislation: it will mean tackling one of the root causes of that crisis: the imbalance of power in the labour market.

A more mellow writer in the Guardian brought up the imagery of the interwar depression:

Of course it is difficult for employers to match the demand to work nine to five and yet also to be served on a 24-hour basis, cheaply and effectively by someone, not them.

But there are other ways to solve this conundrum than indenturing workers or making them wait at the metaphorical factory gate for a tap on the shoulder.

The fixed costs of working

I will start my third blog on the economics of zero-hours by reviewing the economic literature on the fixed costs of working. Helpfully, this literature predicts that zero hours contracts really shouldn’t exist much at all.

The literature on the economics of the fixed costs of work arose out of the economics of retirement and the economics of the labour supply of married women, and in particular of young mothers. This literature was attempting to explain why older workers, or young mothers either worked a minimum number of hours, or not at all.

Fixed costs of working constrain the choices that older employees make about how many hours and days that are worthwhile working part-time. For employees, the fixed costs of going to work limit the numbers of days and number of hours per day that a worker is willing to work part-time. The timing costs of working at scheduled times and a fixed number of days per week can make working fewer full-time days, rather than fewer hours per day less disruptive to the leisure and other uses of personal time.

The fixed costs of working induced older workers to retire completely, and young mothers to withdraw from the workforce for extended periods of time, unless these workers worked either full-time or enough hours part-time each day and through the week to justify the costs of commuting and otherwise disrupting their day and week.

In the case of older workers, there were the fixed costs of commuting and other disruptions to their day. In the case of mothers, there are additional fixed costs of working arising from child care and the commuting and other rather rigid time commitments of picking up and dropping off younger children at school and to day care centres.

The fixed costs of going to work

There is a minimum number of hours of work that will be supplied by different workers that is set by the fixed costs of working. These fixed costs of work arise from commuting time and from dressing and other tasks involved in preparing for the trip to work. These costs are fixed because they do not vary with the number of hours to be worked per day and the amount of effort to be exerted while working (Cogan 1981; Hamermesh and Donald 2007).


A worker will not accept a job offer or continue in a particular job unless they work sufficient hours so that these fixed costs of going to work are recovered along with receiving sufficient reward for giving up pursuing other job openings open now and in the future and for forgoing leisure and the option of making other uses of their time (Cogan 1981; Hamermesh and Donald 2007).

Cogan (1981) estimated that the average fixed time and money costs of married women entering the workforce was 28 per cent of their earnings, and also estimated that the minimum number of hours a married woman was willing to supply in the labour market was 1,300 hours per year.

There may be a preference for fewer working days over fewer hours per day to reduce the time and money costs of going to work. Donald and Hamermesh (2009) estimated that fixed costs of going to work are equal to about 8 per cent of income. The fixed costs of working provide an incentive to workers to bunch activities.

The fixed timing costs of labour market entry

A surprisingly large part of the fixed costs of working comes from disruption in the ability to use spare time effectively (Donald and Hamermesh 2009, 2007). Entering or remaining in the workforce for any time at all significantly affects the effective allocation and enjoyment of time outside of working hours. This disruption to the effective use of the time that is left outside of working hours is the fixed timing cost of labour market entry.

One way to reduce this disruption from entering the labour force at all is to seek to reduce the number of days worked per week rather than the number of hours per day.

Leisure and other private uses of time are displaced if the individual takes or stays in even a small part-time job. Workers must use their reduced amount of remaining free time to catch-up on tasks, often at the weekend that they could have done if they were not working.

Leisure time may be the first to go because many personal tasks can be rescheduled but must be done eventually. These range from cooking, eating, and cleaning to personal upkeep, sleep and rest. Tasks must be hurried or done to a lower quality (Donald and Hamermesh 2009).

Routine – having the same schedule from day to day – saves time (Hamermesh 2005). Routine enables people to economise on the set-up costs of consumption, leisure and going to work.

Entering the work-force for any time at all to work even a small number of hours per day or per week calls for new daily and weekly routines and disrupts many existing routines that make better use of leisure, family and other uses of time (Hamermesh 2005).

Entering the workforce constrains the unfettered use of spare time. Working increases the fixed costs of coordinating family and leisure times. Workers must surround working times with buffers to ensure they are not late for work.

One reality of rising incomes is time become more valuable. A rise in wages raises the value of time because time is a finite and irreplaceable resource. Time cannot be stored or bought and sold but people can try and make better use of it.

With only 24 hours still in every day, the cost of time-intensive activities including working will rise as incomes increase. People shift away from time intensive activities and buy more of those products that are time saving or which are less time intensive to consume. Time is money and this maxim applies with greater resonance as incomes and wealth increase.

Another important fixed time costs of labour market entry is its impact on the efficiency of the remaining time devoted to leisure, household production and other activities when even a small amount of market work is undertaken. Spare time is of much less value if part of every day is to be spent at work.

Fixed timing costs arise because of a need to hurry to get to work on time and forego other activities to be rested for work the next morning. The requirement to attend work blocks out certain days from major other uses of that day and reduces the time available in any day of part-day work for leisure, family time and household production.

Household production refers to the goods and services made at home which could be purchased in the market from a third-party. These include food preparation, cooking, carer obligations, and household cleaning. There are also various other household tasks that must perform for one-self which are essentially personal maintenance and leisure.

Working even a few hours can reduce the worker’s efficiency in household production and other non-market activities and may require the worker to buy goods and services that were previously produced at home. This reduces the net financial rewards of working. Fewer full days of work, rather than fewer hours per day is less disruptive to leisure and the other uses of personal time.

The fixed time costs of market work might induce workers to engage in different mixes of other activities. The additional hours of work during the week affect the allocation of time on a non-working weekend day. They reduce leisure time on weekends and increase weekend time devoted to household production by those who do market work on week days. Workers catch up at the weekend on the household production that the rigidities of their market work prevented them from doing during the week.

Stress is an important fixed cost of working. Workers spend non-market time worrying or thinking about work-problems. Even a few hours of market work will place a worker at risk of some stress.

Floors and ceilings on the structure of the working week

The fixed costs of going to work and the fixed time cost of labour market entry both place constraints on the willingness of workers to accept a job offer involving a zero-hours contract. These contracts must offer something extra over competing job options.

The employer must offer something extra to prospective recruits to induce them to sign a zero-hours contract. There must be something substantial to overcome both the fixed costs of work, such as commuting, and the less obvious but still substantial fixed costs of labour market entry.

Any commitment to work, such as working on a zero hours contract, carries with it significant costs in terms of disruption to the rest of the day, the rest of the working week and the amount of the weekend that is spent on leisure versus resting from work and catching up on tasks that otherwise could have been done during the week but for work commitments.

A zero-hours contract must pay enough over the expected life time of the job to make up for the costs of going to work as well as the disruption and loss of leisure time and also the pure disutility of working before the worker breaks even on working.

As the Unite Union official noted, zero hours contracts appear to be most prevalent in the fast food sector. Job turnover rates in the sector can be several hundred per cent per year.

Many of the workers in the fast food sector, as the Unite union official himself noted, are young. Teenagers and young workers changed jobs frequently, particularly those who are studying part-time or full-time work, injuring the summer.

As such, zero-hours contracts in any particular job will have a short expected life over which the teenager or young worker would have to recoup for the fixed cost of working and the fixed cost of any labour market entry. Employers would have to offer some sort of premium or other implicit guarantee of regular work to induce prospective young recruits to sign a zero hours contract.

The type of workers who will profit from signing a zero hours contracts of those workers with few other demands on their time and flexible days. The workers who might find zero hours contract appealing will be those who do have much routine in their day. Workers who have a considerable amount of routine in their day such as because of family commitments will not find the wage offers in zero hours contracts appealing.

There will be job sorting: workers who have low fixed costs of working and low fixed costs of labour market entry will be attracted to zero-hours contracts.

Employers profit from offering zero hours contracts to workers who don’t want to make a regular commitment to come into work every day. Teenagers and students fall into this category, which makes it less surprising that zero hours contracts appear to be most common in the fast food sector.

There are mutual gains in the fast food sector to both employers and workers from zero hours contracts when there are peaks and troughs in product demand, and some teenagers and young workers have a low cost of coming into work at short notice.

Some economics of zero hours contracts – part 1: concepts, definitions and initial puzzles

Unions say New Zealand employers are following trends overseas and adopting zero hour contracts: workers have to be available for work, but have no hours guaranteed. Unite Union national director Mike Treen said:

McDonald’s, KFC, Pizza Hut, Starbucks, Burger King, Wendy’s – all of the contracts have no minimum hours, and so people can be – and are – rostered anywhere from three to 40 hours a week, or sometimes 60 hours a week, and it depends a lot on how you get on with your manager.

No official figures are available on the number of people on zero hour contracts in New Zealand, but they are are available in the UK in the chart below. About 250,000 workers in the UK work on zero hours contracts.

These workers agree not to work for anyone else, but are not promised regular work at all with their new employer.

The question that must always be asked is why do people who are deemed competent to vote and drive cars sign zero hours contract? What is in it for them? David Friedman asked this question about the economics of restraint of trade agreements for employees:

…the employer who insists on an employee signing a non- competition agreement will find that he must pay, in additional wages or other terms of employment, the cost that the agreement imposes upon the employee, as measured by the employee and revealed in his actions.

It follows that the employer will insist on such an agreement only if he believes that its value to him is greater than its cost to the employee…

The contract is designed, after all, with the objective of getting the other party to sign it.

If I am designing the contract and offering it to many other parties, that may put me in a position to commit myself to insisting on terms that give me a large fraction of the benefit that the contract produces.

But it is still in my interest to maximize the size of that net benefit-which I do by only insisting on terms that are worth at least as much to me as they cost the other party.

The inherent inequality of bargaining power between employers and workers and the reserve army of the unemployed must not be all that they are cracked up to be these days if low paid workers have to sign legally enforceable restraint of trade agreements.

Obviously, the few members of the reserve army of the unemployed lucky enough to have a low pay, insecure job that offers no regular hours today have so many other job options that their employers must get them to agree not to quit and job-hop at will. Jobs must be readily available  to low paid workers for otherwise why do employers insist on this restraint of trade in employment agreements.

Why do workers sign these contracts, which can include a promise of exclusive services – not working for other employers? Several subsequent blog posts will attempt to answer this question

The inherent inequality of bargaining power between employers and workers doesn’t work too well here because  the worker is accepting this job as compared to these other options , which may include employment in an existing job.

Once a worker is on-the-job and has accumulated job specific human capital, issues of post-contractual opportunism come up on both sides.

An important function of the employment contract is to prevent attempts to renegotiate terms and conditions once one side of the other has committed to the relationship and will find it costly to go elsewhere.

Zero hours contracts are negotiated upfront, which makes them unappealing to anyone already has a job, unless the terms and conditions of a zero hour contract, including the wages paid are much more appealing than officious observers make out.

Richard Epstein made this point about the general operation of the labour market, which is of relevance to our search to the answers to the questions posed by this blog post:

Labour markets are not characterized by tricky externalities. They do not pollute streams or require the creation of public goods. They are not characterized by genuine breakdowns in information, as workers are in a position to observe the conditions of their employment on a day-to-day basis.

Left to their own devices, without explicit support from union activities, they will be highly competitive, and thus work hard to allocate scarce human capital to its most productive use.

Workers have the option to quit for higher wages, and employers can always seek out low cost techniques to reduce their labour costs.

Any short-term dislocation for firms or individuals is more than offset by the overall increase in the system productivity, spurred in part by clear signals that should increase investments in human capital.

Zero hours contracts are a new labour market phenomena . That is no reason to automatically default to monopoly explanations for their emergence, including their emergence in a highly competitive industries and highly competitive labour markets where  employees change jobs regularly.

As Coase said in the context of industrial organisation as a whole and novel business practices in particular:

One important result of this preoccupation with the monopoly problem is that if an economist finds something—a business practice of one sort or other—that he does not understand, he looks for a monopoly explanation. And as in this field we are very ignorant, the number of ununderstandable practices tends to be rather large, and the reliance on a monopoly explanation, frequent.

The next blog post arises out of my first exposure to the labour economics of working arrangements. Specifically, how the fixed costs of employment and the fixed cost of going to work  both lead to minimum hours constraints in most employment contracts.

Most of what I know about the  labour, personnel and organisational economics of working arrangements  was about explaining  why employers would expect an employee to work as a minimum number of hours if they were to employ them at all. Always good to start with explanations as to why zero hours should not exist, but they clearly do.

Subsequent blog posts will discuss zero hours contracts in the context of the team production and organisational architecture; and zero hours contracts, equalising differentials and job sorting.

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