How women are disadvantaged in the superannuation system

In a previous blog, I modelled the superannuation contributions of a full-time employee earning $60,000 a year. This employee retires with a superannuation lump sum of $1.1 million

In the first section of this blog I will model a female employee on $60,000 a year who works full-time until she is 29 and when she takes four years off to have her first child,

She returns to work full-time for two years, then takes another four years off when she turns 35 to have a second child. She then returns to work half-time until she turned 60 when she returns to work full-time, in order to boost to superannuation savings, until her retirement at 65.

This is what her employment history looks like in graphical form

At retirement, her lump sum is $780,000, just over 70% of the lump sum of a full-time employee.

The huge advantage of the current scheme is that, for the female employee, her superannuation fund continues earning interest during the periods when she is not working.

However her employment pattern has significant implications for \ her retirement income. You can see the details of the retirement income of the full-time worker in this blog.

On retirement, she can draw down $60,000 a year until she is 85 when her superannuation will run out.

While $60,000 year compares well with her final post-tax salary of $53,000, she is in nothing like the position of the full-time employee whose superannuation lump sum declines only slightly after retirement. When the retiree dies at the age of 85, there is still has $908,000 in his superannuation account. This can become part of his estate and passed on to the children.

This is a luxury that the female superannuation does not have, given her employment history.

If the full-time employee wishes to leave nothing in the superannuation fund and assumes he will die at 85, he can draw a retirement income of $87,000 a year. That’s 34,000 tax-free dollars more than his working income of $54,000 and $27,000 more than a female employee with a different work pattern.

If there is to be a debate about whether superannuation contribution rates should be 9.5% or 12%, it also needs to be a debate about how the superannuation savings of women who choose to move in and out of the workforce or to work part-time, can be supplemented.

How superannuation works: Part 2: Retirement income

One of the toughest problems retirees face is making sure their money lasts as long as they do.

My modelling shows this is not likely to be the case for someone in Australia who enjoys continuous employment between the age of 20 and retirement at 65. 

As a retiree, you also stop paying tax.

After you have been paying into your superannuation fund from the age of 20 to your retirement age of 65, you will stop making contributions and start drawing your retirement income from the superannuation fund.

Retirement incomes are tax-free in Australia. This is a very important element in retirement planning

The contributions side of the model, discussed in an earlier blog, is based on an annual income of $60,000 pa, an annual interest rate of 5%, and a contribution rate of 9.5% pa.

It can be described as a very conservative model.

The model makes no allowance for inflation or cost-of-living rises to make the principles clearer.

There is now a new element to your model: the outflow Retirement income.

In this case, you have opted for a retirement income of $53,000 a year. Your take-home pay after tax on an income of $60,000 a year was $52,750.

The model also assumes that you live to be 90 years old.

In other words, you have a Retirement income equal to your take-home pay was working

The dynamics of this model now look like this:

The interesting thing about this graph is that your super fund continues growing.

This is because your superannuation fund continues to accrue interest while you are receiving your Retirement income.

The interesting thing about these dynamics is that upon your death at the age of 90, there is still money in your super fund.

In fact there is $1.7m still in the account.

There has been discussion in the media from a number of columnists saying that superannuation funds were not designed to provide legacies for children.

But in this case, your estate will benefit by $1.7m which will be given to your dependents.

If you decide you don’t want to leave any money to your dependents, you can decide to empty your superannuation fund of the time you turn 90.

To do this you can draw a retirement income of $78,000 pa.

This is $25,000 a year more than you are earning when you were working. Enough for the occasional overseas trip.

How superannuation works part 1: contributions


How your contributions work

During your working lifetime, your employer will pay into a superannuation account for you at the current rate of 9.5% of your salary. These payments will continue until you retire.

A simple System Dynamics model of your super account during your working life looks like this.

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This model is based on your earning $60,000 year throughout your working life from age 20 to retirement at 65. While this is a simplification of what really happens, it helps to keep things simple in the early stages of an explanation of superannuation.

In this model

Contributions = Salary * Contribution rate

Interest Earnings = (Accumulated) Super * Annual earning rate

The earnings from the stock market are constant at a conservative 5% in the model. Recently stock market returns have been much higher than this. I will discuss the impact of this later in the article.

There are two revenue flows into your superannuation account. The first is your contributions: 9.5% of your salary.

The second revenue flow is the interest earnings on your accumulated superannuation. This will be the earnings rate if the funds are invested in the stock market, as is the case with most superannuation funds.

The contribution that these two flows make is quite different.

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While your contributions have remained stable at $5700 pa, however the interest earnings have risen to just below $52,000 in your final work year. This is because the interest on your account compounds giving the account exponential growth.

As a consequence of this growth, your accumulated super fund now holds just under $1.1 million

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Withdrawing money for a home deposit

There is periodic discussion about allowing first-time buyers to draw on their superannuation for a deposit on their house.

This iteration of the model shows the impact of withdrawing $100,000 for a home deposit at the age of 32.

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As a result, the accumulated superannuation at 65 has now dropped to $434,000, just over 1/4 of the final retirement total, had the withdraw not been.

Such a decline will have a profound impact on your final retirement superannuation payments.

The reason for this dramatic difference is that you go into the final high earning 10 years of your superannuation fund on a much lower base and, as a consequence, the earnings from interest are much lower.

What happens if the earnings rate from the stock market varies

This will make a huge difference to your accumulated superannuation when you retire.

If the simulation varies the returns over the period of investment, particularly in this case varying the rate above 5%, the outcome is quite marked.

Here is rate at which the market returned varies.

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This represents an annual return of 9%, well within the range of the ASX 500 has been performing at over the last 20 years.

The impact of this variation, well above the 5% in the first simulation, is shown in the next graph.

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The accumulated Super is now $3.4 million.

The size of accumulated superannuation funds, such as the one modelled here, raises some important questions about the nature and function of superannuation which will be discussed in a later article.

Dummies’ Guide to Climate Change (ii): Deforestation and the Carbon Sink

The first Dummies Guide to Climate Change laid out the basic structure for the storing of CO2 in the atmosphere. The article then described the dynamics of the relationship between the inflows of CO2 into the atmosphere, the outflows through the carbon sinks and the levels of CO2 that accumulate in the atmosphere.

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This simple model is sometimes called a bathtub model. The inflow is the tap, the outflow is the plughole and the amount of water in the bathtub represents the level or accumulation.

The purpose of these articles is to provide simple models of complex structures and dynamics. To do this,The models built at a high level of aggregation. In this model, the forests that are cut down are replanted as regenerating forests. This is a simplification of the land use that follows deforestation. However, it serves to illustrate the more general principle of the long-term effect of deforestation

The second Dummies Guide to Climate Change drills down into the functioning of the outflow by examining dynamics of carbon storage capacity and deforestation. This sub-model shows the process where forests are cut down (deforestation) and replanted as regenerating forests. Over time, the regenerating forests are restored to their original state. However, there is a decades-long delay before this happens.

Deforestation model and its effect on the carbon sink

Deforestation model and its effect on the carbon sink

The important dynamic here is the impact on the capacity of the land-based carbon sink to absorb CO2. The regenerating forests have some capacity but nowhere near the capacity of the mature forests that have been cut down. The consequence of deforestation is a decline in overall carbon sink capacity.

Change in forests and decline of the carbon sink

Change in forests and decline of the carbon sink

It is generally acknowledged that the world has lost close to 50% of its forests in the last 50 years and that if deforestation continues at its present rate, there may be very few forests left within 50 years. In the last few years, the rate of increase in deforestation has become greater than the rate of increase in population. This is because of the rising affluence of global middle-class and its demand for plant-based products, particularly palm oil.

Deforestation has a double effect on the carbon sink. The first effect is that the burning rain forests increases the CO2 in the atmosphere. The second is that the decreased area of forests reduces the capacity of the carbon sink.

Impact of deforestation on atmospheric carbon and the carbon sink capacity

Impact of deforestation on atmospheric carbon and the carbon sink capacity

This double effect is amplified because it represents an increase in the inflow and a decrease in the outflow leading to a much higher level of CO2 in the atmosphere.

Impact of deforestation on atmospheric CO2 levels

Impact of deforestation on atmospheric CO2 levels

It is clear from the model that the impact of deforestation is significant because of its impact on both the inflows and outflows of the system. It is also clear that action on deforestation will be necessary to avoid catastrophic increases in global CO2 levels. It is also clear from the model that even if the forests are replaced, the delay while they grow means that carbon continues to build up in the atmosphere. It is also clear from the previous model that increasing the landmass and deforestation by a massive 20% only has a minor effect on CO2 levels in the atmosphere.

Tornadoes in Texas

It’s too good an opportunity to pass up.

Recent weather conditions in Texas provide an opportunity to reflect on some of the fundamental aspects of climate change.

 Tornadoes in Texas (actually it was Kansas but I thought Dorothy and Toto would just confuse everybody)

Tornadoes in Texas (actually it was Kansas but I thought Dorothy and Toto would just confuse everybody)

Meteorologist Edward Lorenz  published a paper Deterministic Nonperiodic Flow which developed the work of Henri Poincaré and laid the foundation for chaos theory.

Edward Lorenz

Edward Lorenz

He later presented a paper based on his original work entitled Does the flap of a butterfly’s wings in Brazil set off a tornado in Texas?

The fundamental idea behind this  wonderfully poetic image is that small changes in weather systems can often trigger dramatic and catastrophic events many miles away.

There a number of important concepts underlying Lorenz’s idea.

The first is sensitivity to initial conditions.  Imagine the static charges in a thunder cloud just before you see the lightning. It takes just a very small change in the balance between the positive and negative charges in the cloud to create lightning.

It is helpful to think of sensitivity to initial conditions as a situation where conditions reach a tipping point and things change rapidly. While this term refers to the starting state of the system, it is easier to think of this as the state of a system at any point of time.

This brings us to the second important concept: closely coupled systems. These are systems where each individual element of the system is connected to many other elements and where the interactions between the elements are so numerous, they are difficult to predict.

Hence the butterflies wings in Brazil are part of the conditions that may produce tornadoes in any the part of world.

Earthquakes are another example of sensitivity to initial conditions and closely coupled systems. The tectonic plates that lie beneath the Earth’s surface represent closely linked systems.

 The world's tectonic plates

The world’s tectonic plates

Movements in one part of the structure will reverberate through the system. Every now and then a reverberation occurs at a point that is sensitive to initial conditions and then there is an earthquake. We know that certain areas are earthquake prone but beyond that prediction is exceptionally difficult.

Weather systems share these characteristics. Many of the more spectacular events are triggered by sensitivity to initial conditions: sudden downpours produce widespread flooding such as was seen in Queensland and Victoria.

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While weather systems have always been sensitive to initial conditions, there is now an added component to the dynamics of weather systems:  the burning of fossil fuels.   The heat that is trapped as a result of this has resulted in a large number of systems which exhibit sensitivity to initial conditions being pushed to breaking point.

The polar ice caps are an excellent example of this.

 The melting of the Arctic ice has pushed many with systems to a critical point

The melting of the Arctic ice has pushed many with systems to a critical point

The critical and disastrous effect of this is that  the melting of the ice caps creates a  reinforcing feedback system.

Climate CLD

The loop on the right-hand side of the diagram is the reinforcing system. The more the ice caps melt, the greater the volume of the water in the oceans, the more heat is retained in the oceans, the more the polar ice caps melt.

The critical thing to understand about these positive feedback loops is that their effects do not increase in a linear fashion but exponentially. This means that things start getting bad but then after a while they get really bad really quickly.

And here’s why this happens.

Climate 2

The heat that is trapped in the oceans increases the heat trapped in the atmosphere. This in turn serves to accelerate the melting of the polar ice caps. So there are two impacts on the ice caps: the first is the temperature of the oceans and the second is the temperature of the atmosphere.

But there’s another effect in this closely coupled system.

As the temperature of the atmosphere increases, people use more energy to cool their houses. This in turn increases carbon emissions which increases the trapped heat in the atmosphere. So we now have three reinforcing feedback loops working in this closely  coupled system and all of them are serving to accelerate the rate at which our climate is being degraded.

 How things get worse very much more quickly.

How things get worse very much more quickly.

Our planet is reaching the really-bad-really-quickly state and eventually We will reach a point where nothing we can do will be of any use.

Dummies’ guide to climate change

The UN Intergovernmental Panel on Climate Change has warned of an increase in severe and irreversible damage to the planet if high greenhouse gas emissions continue and the planet warms significantly.

What follows here is an explanation of the total inadequacy of the targets being set particularly those set in Australia. The explanation is built on a very simple little model and the data is taken from the Pro-Oxygenwebsite.

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The technical term for this diagram is a stock-flow-rate diagram. It’s a bit like a bathtub (which is the stock which acts as an accumulation), the inflow of carbon dioxide is like a tap running into the bathtub. The carbon absorbed by land sinks (that is forests) is like a plughole, draining the carbon dioxide out of the atmosphere. The bath tub is currently filling up at a frightening rate.

This is because we are emitting more carbon dioxide than the land sinks can absorb. What is not absolved is stored in the atmosphere and in the oceans.

Here’s a graph that illustrates the problem.

Gap 2

This graph shows the gap between what is being emitted and what is being absorbed. This amount is the amount that is pumped into the atmosphere every year. While the absorption is patchy it is relatively consistent while the emissions continue to rise.

Politicians and the media focus on the amount that we have to reduce the amount of emissions. But this is not what we must be concerned about. It is the total accumulation of carbon dioxide in the atmosphere that is going to destroy the environment.

The trick to solving the climate change problem is to get the amount we are emitting below the capacity of the land sinks to absorb CO2. It is not until we have done this that the total amount of CO2 in the atmosphere will begin to decline.

Australia currently has a goal of reducing carbon emissions by 5% by 2020. It is unclear what the goal will be beyond that. But here’s a picture of what reducing CO2 emissions global by 5% in 2020 will do.

5pc

Compared with the  “no action” scenario, there is a slight but almost imperceptible change in the total accumulation of CO2.

There is talk of setting a target of 15% by 2020. The following graph shows the impact of this target.

15

As you can see, we are still not making any progress. Atmospheric carbon levels are still rising which really makes the debate about a target of 5% or 15% pretty much irrelevant.

So what is it going to take to deal with this problem. The next graph shows a reduction of 40% from 2020. This is the level suggested by a recent conference of scientists in Europe.

For simplicity’s sake, and to demonstrate the magnitude of the change required, I’ve shown the effect of all at once. A more realistic approach would be to achieve this target over a number of years, but it would still need to be a total of an 80% reduction whatever time period is used.

80

It has been possible to achieve this result because the level of carbon emission is down to level that can be absorbed.

in out

This level of reduction will maintain total CO2 in the atmosphere at current levels. A level that the UN Intergovernmental Panel on Climate Change says will include more coral bleaching of the Great Barrier Reef; declines in rainfall in southern NSW and Victoria and a 20-40% increase in Melbourne days over 35 degrees by 2035.

Clearly, we are not getting a 80% reduction in emissions starting in 2014 but this does illustrate the magnitude and seriousness of the problem and certainly that the 5% target by 2020 will be woefully inadequate.

The other approach to the problem is to increase the capability of the land sinks to absorb CO2. The following graph shows the impact of an immediate 20% increase in the Earth’s ability to absorb CO2 namely, a 20% increase in total global forestation.Again, this is shown happening immediately but clearly a 20% increase in global forestation will take a millennia, time we might not have.

This does not have as great an impact as cutting emissions but under the combined scenarios total CO2 in the atmosphere is finally declining. To achieve this we must have an 80% reduction in emissions starting in 2014 and at 20% increase in forestation, also starting in 2014.

Yes, the problem is that serious and that intractable.

But not if you’re a Prime Minister whose views of climate change seem to be based on some doggerel that was written by a 22-year-old member of the landed gentry at the beginning of the last century.

Dorothea Mackellar loved a sunburnt country and as far as Tony Abbott is concerned things haven’t changed much since she wrote My Country.

Tony Abbott's climate adviser Dorothea Mackellar

Tony Abbott’s climate adviser Dorothea Mackellar

‘Australia’s a land of droughts and flooding rains, always has been, always will be,’ said Abbott in a comment that would be laughable if it were not so tragic.

A touch of realism enters the climate debate

Opposition Leader Bill Shorten on Friday confirmed Labor is seeking a 45 per cent reduction in dangerous emissions by 2030, contingent on consultation with industry and the community, saying proof of global warming is irrefutable and the government’s policies are “pathetic” and an “expensive joke”.

It’s good that Shorten is at last looking at reductions in emissions that are and increase on the woefully inadequate target set by the Turnbull government .

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 Bill Shorten is thinking about climate change but not hard enough

 The definition of the problem is quite simple.

 If we wish to stop global warming at its current level, then we need to make the rate at which carbon dioxide  and methane are emitted equal to the rate at which they are absorbed by the oceans and forests.

 If we want to improve matters, then the rate of emission needs to be less than the rate of absorption.

 It can be explained very simply in this stock/flow diagram.

To maintain the status quo:

 Carbon into the atmosphere = Carbon out of the atmosphere

 To improve things:

Carbon into the atmosphere < Carbon out of the atmosphere

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My modelling of the need for reductions in emissions is on my blog: Dummies’ guide to climate change and Dummies’ Guide to Climate Change (ii): Deforestation and the Carbon Sink

The modelling demonstrates that:

Clearly, we are not getting the required 80% reduction in emissions starting in 2014 but this does illustrate the magnitude and seriousness of the problem and certainly that the 5% target by 2020 will be woefully inadequate.

The other approach to the problem is to increase the capability of the land sinks to absorb CO2  namely, a 20% increase in total global forestation. 

This does not have as great an impact as cutting emissions but under the combined scenarios of carbon reduction and absorption capability increase, total CO2 in the atmosphere is finally declining. To achieve this we must have an 80% reduction in emissions starting in 2014 and at 20% increase in forestation, also starting in 2014.

So far the response to the labour proposal has been predictable.

The Australian reports Former Reserve Bank board member Warwick McKibbin as saying:“At the moment, Australia is contributing a greater economic loss than other countries with the 26-28 per cent target. To be going further out in front is not good policy.”

We should stop being so concerned about the cost of dealing with problem of rising sea levels and drastically altered climate patterns and start talking about the cost of not doing anything or doing too little.

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The vast proportion of Australia’s population live in the coastal areas. Rising sea levels will be a problem for everyone, not just the Gold Coast.

A simple idea for the emission targets

Bill Shorten has restarted the debate on emissions targets immediately before the United Nations conference in Paris.

The debate about emissions targets is always couched in percentage terms which makes it easy for the opponents of any form of reduction to argue that Australia’s emissions are amongst the lowest in the world in absolute terms so were not really  a large part of the problem. However, our emission rates are amongst the highest on a per capita basis.

So here’s an idea.

Each nation needs to provide carbon sinks at least equal to their emission rates. In addition, each nation will be allowed credit for an area of ocean (which absorbs carbon dioxide) equal to its landmass.

SINK.jpeg

This will set equitable goals for carbon reduction rather than simply insisting that people produce by 45% by 2030 etc.

It shouldn’t be too difficult to do the sums.

Getting agreement may be more difficult. China and America are going have to accept a large amount of the responsibility for controlling climate change.

But this system allows a measurement that will circumvent many of the arguments of the climate deniers, particularly in Australia.

It’s probably not going to cut much ice with Trump administration in the US, but have come get into the White House, logic and reason will go out the door.

Population growth: the villainous elephant in the room

The decision by the Chinese government to abandon the one child policy throws into sharp focus one of the crucial drivers of global warming and climate change: population growth.

one child

There is much debate about the effectiveness of the policy and it certainly had severe implications for the human rights of the Chinese population. But this change also has huge implications for population growth and climate change.

In all the discussions of climate change, the focus is on finding ways to stop industries polluting the environment. No one stops to ask why they pollute the environment.  They are meeting a demand for goods and services that returns profits and this demand will continue to grow as the global population grows and the affluence of the middle classes increases.

Carbon emissions from coal-fired electricity generators are only a symptom of the problem which is humanity’s growing demand for electricity. This demand is directly related to a population  that continues to grow exponentially.

Unless we can control the population of the planet, no amount of restriction on carbon emissions is going to have much impact on global warming or climate change.

The basic model that I have always used for population growth is a simple stock/flow model:

carbon

The two flows are like a tap and a plug hole in the bath tub. The square box in the middle is the bath tub where water, or in this case carbon dioxide, builds up. If emissions are greater than the absorption, then the amount of carbon in the atmosphere increases. And this will be the case until emission reductions go well beyond 40%.

To reduce the amount of carbon in the atmosphere, absorption needs to be greater than emissions. I have set out the dynamics of this in two posts:

Dummies’ Guide to Climate Change (ii): Deforestation and the Carbon Sink

These posts discuss the dynamics of climate change but have not included a discussion of population growth. In fact the fundamental dynamic driving climate change if this diagram.

model

 Carbon emissions up are driven by global population and down by government efforts. The problem is that global population will dwarf the puny efforts of governments.This problem is likely to be exacerbated by the fact that China has abandoned its one child policy. Because no one is certain how effective the policy was in restricting population growth it is impossible to predict the impact of the abolition of the policy beyond the fact that it will almost certainly lead to a much greater rate of population growth.

pop cc

So this is what the problem looks like:

Despite even the best efforts of governments, population growth will still be the major driver of climate change and unless we can do about this problem, the outlook is very bad indeed.

Will implementing Prof Fels’ recommendations improve taxi services for Victorians?

The State government has now received the final report from the Taxi Industry Inquiry. While there is some conjecture about the impact of the recommendations, there is agreement on one aspect. Reducing the cost of the taxi licences will destroy the capital value of the current licence holders. The future value of the existing licences is a matter for debate but it will certainly be considerably less than the $450,000 that they currently command in the marketplace.

There is also general agreement that the payments to taxi drivers are far too low and there is anecdotal evidence that this is beginning to affect the availability of drivers and the availability of taxis. Reducing the annual cost of a taxi licence will decrease taxi costs and increase revenue per taxi for licence holders whether this translates to increase payments to taxi drivers depends on the extent to which the licence holders pass the cost savings on.

We have drawn a causal loop diagram (CLD) that serves as a model for our dynamic simulation of the proposed changes. In this model, the arrows indicate the causal relationships that demonstrate the interconnected and dynamic structure of the taxi industry.

The starting point in the model is the Price of taxi licences (shown in red). As the price goes down, the number of taxis will go up, as will revenue per taxi. This is indicated by the letter O at the end of the arrow meaning the variables move in the opposite direction. This means that dropping the price of licences will increase the revenue but also increase the number of taxis. More taxis means that the revenue per taxi will go down.

As the number of taxis goes up, the waiting times come down (also indicated by an O). The report argues that as waiting times come down, demand will go up (again, indicated by an O).  This increased demand will lead to an increase in the revenue per taxi. This, there are two influences on taxi revenue: increased demand, which will increase revenue and more taxis which decrease it.

Taxi revenue is currently the sole determinant of the driver payments. If taxi revenue declines, driver payments decline and the number of drivers will also decline. This will lead to fewer, not more, taxis on the road.

The first iteration of the model began with taxi numbers increasing, but the model suggests that taxi numbers may actually decrease until the market finds a new equilibrium.

With a taxi numbers declining as a result of driver shortages and declining revenue, we find that waiting times go back up, demand goes down and revenue per taxi declines even further. The counterintuitive conclusion that arises from the dynamics described in the model is that reducing the price of taxi licences is likely to have a long-term and detrimental effect on the industry.

It is not known how many new taxis will enter the market. However, unless existing licence holders drop their annual leasing fee to equal the government’s new annual taxi licence cost, then all existing leaseholders, some 5000, would apply for the new government licenses. This will mean that the existing licence holders and holders of the new government licenses will be competing for a decreasing pool of drivers.

The other policy option open to the Government is to increase the revenue by increasing fares. Fare increases have a twofold impact, they increase the revenue per taxi but they decrease the demand. At best, this policy is likely to have little or no impact on the overall dynamics and profitability of the industry.

The conclusion is clear. Decreasing the price of taxi licences and increasing fares is unlikely to have long-term beneficial effects within the industry. It will be necessary to bring about significant systemic and structural change to do this.

Our detailed simulation modelling can show the impact of differential fares for peak hours and short trips, changes in regulations regarding zoning and changes to the balance between fares and flag falls. It can also show the impact of linking license fees to improvements in quality.