VoxDev Development Economics

By 2018 the reservoirs supplying Cape Town were down to 20% of capacity. If they reached 13.5%, the city would need to shut down parts of the water network and send residents to collection points to fetch water. That was known as Day Zero, and the rain came just in time to avoid it.
Hugh Cole (City of Cape Town) joined the city government in the middle of the crisis, and has subsequently driven the use of data for many aspects of city planning, not just for water. Cape Town now runs its own household survey, works with a private sector partner to measure net migration, and randomises the rollout of water meters so it can find out how they change behaviour. It also runs trials on its electricity subsidy to check whether the money reaches the households it is meant to reach. 
Cole tells Tim Phillips how the Day Zero near miss changed how the city's leadership uses evidence, and how other cities can follow the same path.
The research behind this episode:
Abajian, Alexander C., Cassandra Cole, Kelsey Jack, Kyle C. Meng, and Martine Visser. 2025. "Dodging Day Zero: Drought, Adaptation, and Inequality in Cape Town." NBER Working Paper 33468.
Cole, Hugh, Kelsey Jack, Derek Strong, and Brendan Maughan-Brown. 2020. "City of Cape Town, South Africa: Aligning Internal Data Capabilities with External Research Partnerships." In Handbook on Using Administrative Data for Research and Evidence-based Policy, edited by Shawn Cole, Iqbal Dhaliwal, Anja Sautmann, and Lars Vilhuber. Cambridge, MA: Abdul Latif Jameel Poverty Action Lab.
To cite this episode:
Phillips, Tim, and Hugh Cole. 2026. "Cape Town's day zero: How data rebuilt a city's water resilience." VoxDev Talks (podcast).

About the guest

Hugh Cole is Director of Policy and Strategy and Chief Data Officer at the City of Cape Town, where his department covers strategic policy, strategic planning, research and economic analysis. He is a Visiting Senior Fellow at the School of Public Policy at the London School of Economics. Before joining the city in 2017 he was Director of Country Programmes at the International Growth Centre, running teams in 14 countries across sub-Saharan Africa and South Asia.
Research cited in this episode

Day Zero. The term began in the media as the day Cape Town's taps would run dry, then settled on something more specific. It became the day dam levels would hit 13.5%, at which point the city planned to shut down parts of the reticulation network and open water collection points, sequenced so that the most vulnerable communities were affected last.
Dodging Day Zero. Abajian, Cole, Jack, Meng and Visser use municipal billing records to show what the emergency measures did to different households. Before the drought, richer households used twice as much piped water as poorer ones; at the peak of the crisis they used less, partly because they could drill boreholes and substitute private groundwater for the public supply. That eroded the utility's revenue and shifted the cost of supply towards households who could not afford a private alternative, which is why the tariff reform that followed matters as much as the conservation campaign did.
Zonal water balance assessment. Pressure management in the network was one of the two measures Cole credits with the largest effect during the drought, alongside communication with residents. Managing pressure means knowing the boundaries of each pressure zone, and those boundaries had drifted over years of pipes being added and not always recorded. The remapping exercise that followed compares water entering a zone with water leaving it, and it is still going on.
The Green Dot map. During the drought the city published a neighbourhood level map of household water consumption, developed with academic partners including Martine Visser at the University of Cape Town. Households within their usage band showed as a green dot. The aim was peer pressure at street level rather than a citywide number.
The Water, Air and Energy Lab. Launched in March 2024 by J-PAL Africa at the University of Cape Town, the City of Cape Town and Community Jameel, the WAE Lab pairs city policymakers with researchers to run randomised evaluations on clean air, water and reliable energy. Kelsey Jack is its scientific advisor. It is part of a network of J-PAL air and water labs that also includes national and state level labs in Egypt and India.
Free basic electricity. Cape Town subsidises electricity for low-income households, targeted using thresholds on property value and consumption. Because eligibility turns on a cutoff, households just above and just below it are otherwise similar, which lets researchers separate the effect of the subsidy from everything else that differs between rich and poor households. The city funds this transfer from its own budget rather than through National Treasury grant regimes.
Advanced metering infrastructure. The city is replacing water meters with digital ones to improve billing accuracy, revenue recovery and leak detection, and to see whether more frequent consumption information changes what households use. Contractor capacity and budget mean the rollout has to be phased, and the phasing is what makes randomisation possible.
Charging ahead. An earlier Cape Town collaboration with the same origins. Jack, B. Kelsey, and Grant Smith. 2020. "Charging Ahead: Prepaid Metering, Electricity Use, and Utility Revenue." American Economic Journal: Applied Economics 12(2). Over 4,000 customers were switched from monthly billing to prepaid meters in a randomised order; electricity use fell by about 13%, and the utility recovered more of its revenue on time.
Non-revenue water. Water that is produced and then lost before it can be billed, mostly through leaks. It is a persistent problem for utilities across the continent, and separating the leak detection effect of new meters from the behavioural effect on households is one of the questions the city wants answered.
Data protection. South Africa's Protection of Personal Information Act is the law Cole refers to as the local equivalent of the European Union's GDPR. It governs what the city can share, and it is why partnerships with banks and telecommunications firms on the informal economy are framed around aggregated and anonymised data.
More VoxDev Talks episodes

Minibuses, major gains: Rethinking urban transit in developing countries. Lucas Conwell on the privately run minibus networks that Cape Town depends on, and the policy tweaks that would make them work better. Cole describes the city's own minibus taxi reform programme in this episode.
The role of cities in economic development. Edward Glaeser and Diego Puga on why the cities of the developing world are the place to look. Cole quotes Glaeser twice here, so this is the natural next listen.
How AI can put 20 years of development evidence to work. Iqbal Dhaliwal of J-PAL on why new technology only helps when it is attached to an existing evidence base.
Related reading on VoxDev.org

Avoiding day zero: Drought and water pricing in South Africa. The authors of the paper set out how private adaptation by wealthy households undermined the utility's ability to cross-subsidise everyone else, and what the tariff reform did about it.
Charging ahead: Prepaid metering, electricity use, and utility revenue. Kelsey Jack and Grant Smith on the Cape Town prepaid metering trial, and what it means for utilities trying to serve low-income customers.

In 1978, a farmer in rural China could not sell a sack of grain above the state quota, choose an employer, or move to the nearest city without a permit.
In this week's VoxDev Talk, Kaiji Chen and Tao Zha (both Emory University and Atlanta Fed) explain how China dismantled barriers like this one at a time. Gradualist reform first gave farmers the right to sell surplus grain at market prices. Small state firms were privatised 19 years later, while the largest kept state backing. This style of reform powered two distinct growth engines: first, labour moving off the land, then a wave of capital into infrastructure and property. The result: half a century of unprecedented growth -- but it also produced the debt, inequality and trade tension now working against China's growth model.
The research behind this episode:
Chen, Kaiji, and Tao Zha. 2025. "China's Macroeconomic Development: The Role of Gradualist Reforms." Journal of Economic Literature 63 (4): 1331-62.
To cite this episode:
Phillips, Tim, Kaiji Chen, and Tao Zha. 2026. "Fifty years of Chinese growth: The gradualist reform strategy explained." VoxDev Talk (podcast).

About the guests

Kaiji Chen is Professor of Economics at Emory University and a research fellow at the Federal Reserve Bank of Atlanta's Center for Quantitative Economic Research. His research spans financial contracts, business cycles and China's macroeconomy, with recent work on housing policy, credit allocation and household consumption in China.
Tao Zha is the Samuel Candler Dobbs Professor of Economics at Emory University and executive director of the Center for Quantitative Economic Research at the Federal Reserve Bank of Atlanta. He is a research associate at the National Bureau of Economic Research and was elected a Fellow of the Econometric Society in 2017. His research spans macroeconomics, financial economics and econometrics, with a long standing focus on China's economy.
Research cited in this episode

The household responsibility system. Piloted in Sichuan and Anhui from 1978 and adopted nationwide by 1980, this reform kept land collectively owned but contracted it to individual households, who could sell output above a fixed state quota at market prices. It replaced work point pay with a direct link between effort and income, and the productivity gains it released freed the rural labour surplus behind China's first wave of industrialisation.
Township and village enterprises (TVEs). Rural, collectively owned firms that absorbed workers leaving agriculture through the 1980s and 1990s, often with local governments acting as guarantors for bank credit the firms could not secure alone. TVE employment grew from 28 million in 1978 to 135 million by 1997, and TVE output rose from under 6% of GDP to 26% over roughly the same period.
The hukou system. China's household registration system, introduced in 1958, ties access to housing, healthcare, education and grain rations to a person's registered location, rural or urban. It made moving to a city without an urban permit practically impossible. Restrictions eased in stages from the late 1990s, and the formal rural urban distinction was removed nationwide only in 2014.
"Grasp the large, let go of the small." The policy, initiated in 1997, under which China privatised or allowed the bankruptcy of small and medium state owned enterprises while retaining state control of the largest, most capital intensive firms in sectors such as infrastructure, energy and real estate.
WTO accession and permanent Most Favoured Nation status. China joined the World Trade Organization in 2001. From 2002, permanent MFN status with the United States removed the annual threat of tariff spikes on Chinese exports, a stability that Chen and Zha's paper credits with accelerating China's shift from labour intensive exports toward electronics and other capital intensive goods.
The 2009 stimulus and local government financing vehicles. In response to the global financial crisis, China launched a four trillion RMB fiscal package alongside a sharp expansion of bank lending. Much of the resulting infrastructure spending ran through local government financing vehicles, off budget entities set up to borrow for public projects; the debt they built up is now central to China's financial stability risks.
Total social financing. International Monetary Fund. 2026. "People's Republic of China: 2025 Article IV Consultation." IMF Country Report No. 26/044. The IMF's broadest measure of credit in the Chinese economy, the figure Kaiji Chen cites as roughly 315% of GDP in 2025.
More VoxDev Talks episodes

The Four Pests campaign and China's Great Famine, in which Shaoda Wang traces a darker chapter of Chinese economic history, the mass eradication of sparrows during the Great Leap Forward and the millions of deaths that followed.
The rise and fall of China's overseas lending, in which Sebastian Horn explains how China became the developing world's largest bilateral creditor, and why that lending boom has now gone into reverse.
Related reading on VoxDev.org

The Mandarin model of growth, on how China's system of promoting local officials for delivering growth shaped decades of investment led expansion.
How China became the world's factory: Trade, industrial policy, and growth, on the trade liberalisation and industrial policy that took China from export processing to global manufacturing leader.
The bubble dynamics of China's housing boom, Edward Glaeser on the construction surge behind the price rises Chen and Zha describe in this episode.

The ballot cast by a landless labourer counts the same as the one cast by the landlord whose fields he works. In this way, democracy can give excluded or subordinate groups access to political power.
That's not what has happened, at least, not in large parts of the Global South. Amit Ahuja (UC Santa Barbara) calls those at the bottom of the social order "subaltern groups". Three barriers stand between their votes and any lasting gain. Violence that goes unpunished. The erasure of their shared culture and history by those in power. And they have too little money and organisation to campaign for their rights.
The evidence shows that since 2014 the gains that these groups made in the previous three decades have started to reverse, he warns. The old hierarchies are reasserting themselves.
The research behind this episode:
Ahuja, Amit. 2026. "Subaltern Mobilization in the Global South." Annual Review of Political Science 29: 391-411. Open access.
To cite this episode:
Phillips, Tim, and Amit Ahuja. 2026. "Caste, race, and power: The barriers to political inclusion." VoxDev Talks (podcast).

About the guest

Amit Ahuja is Associate Professor of Political Science at the University of California, Santa Barbara, with research spanning ethnic parties and movements, military organisation, caste, and the politics of inclusion and exclusion in multiethnic societies. His book Mobilizing the Marginalized: Ethnic Parties Without Ethnic Movements won the 2020 Kamaladevi Chattopadhyay NIF Book Prize. He co-edited Internal Security in India: Violence, Order, and the State with Devesh Kapur.
Research cited in this episode

Subaltern. The word means "of inferior rank" and was used by Antonio Gramsci in the Prison Notebooks to describe groups subordinated by a ruling elite. Ahuja gives it three working attributes: a stigmatised identity acquired at birth, disproportionate poverty, and disadvantage that passes from one generation to the next.
Ranked and unranked social orders. Donald Horowitz, in Ethnic Groups in Conflict (1985; University of California Press, 2000 edition), separates societies where groups sit in a vertical hierarchy from those where they sit side by side. The Hausa-Fulani, Igbo and Yoruba in Nigeria, and Maronite Christians, Sunnis and Shia in Lebanon, compete without one being formally subordinate to another. Hierarchy is not a universal feature of diverse societies.
Greed against grievance. Paul Collier and Anke Hoeffler argued in 2004 that people join insurgencies to capture resources such as diamonds or minerals; Ted Gurr's Why Men Rebel (1970) argued instead that rebellion follows the gap between what people have and what they expect. Ahuja adds a third answer drawn from ethnography.
The dignity of insurgency. Elisabeth Wood's study of El Salvador (2003) and Alpa Shah's work on Maoist central India (2013) both find that the poor support armed movements partly because insurgents treat them better than landlords and state officials do. Participation confers dignity in a setting built to deny it.
The identity penalty. Devorah Manekin and Tamar Mitts (2022) find that nonviolent campaigns led by marginalised groups attract less popular participation and fewer elite defections than comparable campaigns led by dominant groups. Nonviolence works, but not equally well for everyone.
Undocumented rights. Afro-descendant communities on Colombia's Pacific coast, the San in the Central Kalahari, and Adivasis in India's forests all hold customary claims that colonial and postcolonial registries never recorded. Without a written record they are reclassified; Adivasis became "encroachers" under British forest law and the conservation regimes that followed.
The Dalit Panthers. Formed in western India in the 1970s, the group combined revolutionary politics with armed self-protection for Dalits facing caste violence, taking its name and some of its style from the Black Panther Party.
Military service as a school for organisers. Black South Africans recruited during the Second World War, and Dalits taken into the British Indian Army during the world wars, both emerged with leadership training and a more assertive political style. Dominant groups are usually reluctant to arm subaltern populations; labour shortages force the question.
The Indian Election Commission. Amit Ahuja and Susan Ostermann (2018) trace how the commission secured polling stations through the 1990s and 2000s, which made it possible for parties to bring marginalised voters to the poll. Institutional autonomy, backed by the courts, can partly offset a coercive environment.
Co-optation in Bolivia. Movimiento al Socialismo absorbed parts of the country's Indigenous movement and blunted its radical edge. Alignment with a party brings resources and patronage positions; it can also cost a movement its original demands.
More VoxDev Talks episodes

Can contact between groups reduce prejudice? Matt Lowe on why decades of evidence for the contact hypothesis look weaker under preregistration, and why prejudice does not simply fade with development.
Caste, identity, and worker productivity in India Daniel Keniston on how caste still sorts Indians into occupations, and what the economy loses because of it.
Related reading on VoxDev.org

Something to complain about: How minority representatives overcome ethnic barriers, on a formal complaints system in Bihar that gave Scheduled Caste ward members leverage over village heads who were holding up their projects.
How expanding voting rights shaped politics in India. Franchise expansion in 1935 and 1950 barely moved turnout or competition, and yet it shifted public spending towards the newly enfranchised.
No representation without reservation: The long-term limits of gender quotas in India, on what happens to descriptive representation once the quota is withdrawn.

Do economists treat what men do as normal human behaviour, and then study norms around women as a departure? If so, we need to pay more attention what we mean by masculinity.
That's what Pauline Grosjean (University of New South Wales, CEPR) does. She argues that these masculinity norms carry economic weight of their own. What do men around the world think "being a man" means? The consistent answers: winning against other men, self-reliance, control over women, aggression, and the avoidance of anything coded as weak or homosexual. Grosjean and her co-authors measure adherence to these core dimensions across 70 countries. How do these beliefs vary by age, economic development, and culture? And what do they predict about the way men will behave?
The research behind this episode:
Matavelli, Ieda, Pauline Grosjean, Ralph De Haas, and Victoria Baranov. 2026. "Masculinity Norms and Their Economic Implications." Annual Review of Economics 18:127-55.
To cite this episode:
Phillips, Tim, and Pauline Grosjean. 2026. "Masculinity norms and their economic implications." VoxDev Talks (podcast).

About the guest

Pauline Grosjean is a professor in the School of Economics at the University of New South Wales and a fellow of the Centre for Economic Policy Research. Her research spans culture and institutions, gender roles, violence and conflict, and how historical conditions shape economic behaviour long after those conditions have gone.
Research and concepts cited in this episode

Masculinity norms. Social expectations about how men should behave, or how a "real man" should behave. Grosjean draws the distinction from gender-role norms, which define men relative to women. Masculinity norms are largely about how men rank against other men. The five core dimensions measured in the survey are the importance of winning and status, self-reliance and help avoidance, violence, power over women, and avoidance of homosexuality.
Global Masculinity Survey. The 70-country survey behind the review, built on measurement tools developed by social psychologists and run in partnership with the European Bank for Reconstruction and Development across its countries of operation, then extended to a further 32 countries. See De Haas, Ralph, Victoria Baranov, Ieda Matavelli, and Pauline Grosjean. 2024. "Masculinity Around the World." CEPR Discussion Paper 19493 (gated).
Male-biased sex ratios in colonial Australia. Grosjean's earlier work uses convict transportation, which left parts of Australia with far more men than women, as a natural experiment. Areas that were historically male-biased show stronger masculinity norms today, more violence and male suicide, and weaker support for same-sex marriage; the last of these puzzled economists, because a shortage of women should, on a supply-and-demand reading, make men more relaxed about other men's homosexuality, not less. See Baranov, Victoria, Ralph De Haas, and Pauline Grosjean. 2023. "Men. Male-Biased Sex Ratios and Masculinity Norms: Evidence from Australia's Colonial Past." Journal of Economic Growth 28:339-96.
Ten to Men. An Australian longitudinal study of male health that measures both adherence to masculinity norms and a range of self-reported violent behaviour. Grosjean cites its strong associations between norm adherence and interpersonal aggression, sexual violence and self-directed harm.
Testosterone and status seeking. The link often assumed to run from testosterone to aggression is, on the evidence, better read as a link to status seeking, with aggression only one of its possible expressions. Testosterone itself responds to social context, diet and caregiving, so it sits inside the culture rather than outside it.
Misperceived norms. Men often overestimate how strongly other men endorse restrictive norms, and also misjudge what women want, believing women approve of controlling or emotionally closed behaviour when they do not. Grosjean links this to Marianne Bertrand's work on men declining paternity leave for fear of others' disapproval, and to the gender-segregated online spaces of the manosphere, where the norms are advertised and reinforced.
School intervention in Brazil. An ongoing trial with Ieda Matavelli comparing two approaches in schools, one closer to cognitive behavioural therapy and one that directly tackles beliefs about what it means to be a man. Matavelli's earlier work documents how warped young men's views of others' expectations can be, and tests whether correcting them changes behaviour.
More VoxDev Talks episodes

Non-elite women in politics. Soledad Artiz Prillaman on how patriarchal norms and social networks shape which women can take part in politics, and why a seat count tells you little about power.
Paid work for women and domestic violence. Deniz Sanin on how the spread of coffee mills in Rwanda gave women paid work and, with it, less violence at home.
Related reading

Masculinity norms and their economic consequences, a VoxEU column by the four authors setting out how these norms shape labour markets, health, education, households and politics, with the country and individual-level survey findings.

This is an episode from VoxDev's new podcast series, Ideas in Development. This series has a separate podcast feed, where you can find every episode of Oliver Hanney’s conversations with leading development thinkers.
YouTube: https://www.youtube.com/watch?v=jgwcv4fyU28 
Apple Podcasts: https://podcasts.apple.com/us/podcast/how-global-supply-chains-are-built-and-how-to/id1866874059?i=1000774798943 
Spotify: https://open.spotify.com/episode/5EECcLVxxEQtkX3gJZcHGH?si=94e15ed7834a4e86 
Audioboom: https://audioboom.com/posts/8922412-how-global-supply-chains-are-built-and-how-to-actually-attract-investment 
Substack: https://ideasindevelopment.substack.com/p/how-global-supply-chains-are-built 
Bill McRaith spent his career building supply chains – from 1980s Britain, to a factory in Panyu, China in 1990, to Ethiopia three decades later. He joins Oliver Hanney to explain what really attracts manufacturing investment to a developing economy, and why the model most countries are targeting no longer exists.
In this wide-ranging conversation we cover why China’s industry grew; why responsive local governments beat tax holidays; the collapse of the wage gap; how Ethiopia was chosen as a beachhead; and why apparel remains the right first-mover industry for countries not yet on the industrialisation road.