Beatriz Armendáriz and Jonathan Morduch, The Economics of Microfinance

slaniel | Economics of Microfinance, The | Saturday, April 19th, 2008

Cover of _Economics of Microfinance_: painting of a woman toiling away, seemingly rolling out tortilla or something similar Microfinance is most famous as microlending, whose most famous representative is Bangladesh’s Grameen Bank. Grameen, and its founder Mohammad Yunus, won a Nobel Peace Prize in 2006 for their aid to the poor. The idea, with which most people are probably familiar, is that the bank loans some of the world’s most destitute people small amounts of money — $100 or less, typically — for some vital bit of capital. Borrowers might use the money to buy a sewing machine, for instance, which they can then use to produce far more clothing than they had produced by hand. Grameen’s default rate has been remarkably low — “the poor always pay back”, to use the phrase from Grameen II.

The economic logic here is actually revealing as a study of what’s unspoken in economic logic, hence how misleading economic postulates are. “All else being equal” (such a magical phrase), the first bit of capital that I get will yield more benefits to me than the second bit. Assuming I’m rational, I will spend the first money I get on more-productive capital, then spend subsequent bits on less productive capital. That is, the marginal returns to capital are decreasing (or at least nonincreasing). Hence, if I’m a rational bank and all else is equal, I should be more willing to lend to the poor than to the wealthy: I’ll get a greater return from lending that little bit of capital.

Needless to say, that’s not how it works: Citibank is in no rush to lend to Bangladeshi farmers. Why not? Obviously it’s because all else is not equal. Among many other things, Citibank relies on the vast infrastructure provided by advanced capitalist economies: before they loan to me, they check with credit-reporting agencies that have a special competence validating people’s reputations. Those credit-reporting agencies can follow me around because I was born with a number, namely a Social Security Number, which I can’t escape from without some work. Hence the infrastructure beneath me makes it hard for me to default on a loan without other banks noticing. This infrastructure is missing from Bangladesh. Consequently, the cost of gathering all the necessary information about a loan applicant is much higher — transaction costs per dollar of loan are astronomical if the loans are administered in the way that Citibank specializes in.

Grameen handles this in a novel way, for which they’re justly famous. It’s called “group lending”: in Classic Grameen, they loan to groups of five people. If any one of the applicants defaults, the others are forbidden from ever receiving loans again. The informational burden is transferred from the bank onto the applicants.

Can’t those five people conspire to default on loans together? Yes, they surely can, and here we run into another difficulty of the classic economic picture. If they cut and run on a loan, they could run to another microlender and get another loan — and so on for as long as they want, so long as the microlenders don’t share information. The more microlenders that service a given area, the more challenging this problem becomes. So competition actually works against microlenders here, by making collusion possible. To solve this problem, microlenders need a set of institutions that make validating reputations less costly. Credit-reporting agencies would help, as would the whole arsenal of Western identity policies. Which isn’t to say that those are the only systems that will solve microlenders’ problems, by any means; just as group lending is a novel approach to the developing world’s specific problems, so we might expect them to land on different solutions to the reputation problem.

The Economics of Microfinance is filled with interesting discoveries like this. It starts with a less-developed form of microlending, namely the Rotating Savings and Credit Association, evolves through group lending, and discusses where Grameen and its ilk (BRAC et al.) are today. Most interesting for me was microsaving, as opposed to microlending. The poor often need savings accounts more than they need loans. Indeed, they are willing to receive negative interest rates on their money, just to ensure that the money stays in a safe place. Armendáriz and Morduch give a remarkable example: in certain rural villages, savings collectors will offer to take money out of the villagers’ hands, hold it for a time, take a fee, and return the now-smaller pile of money. Presumably this negative interest rate is less negative than the alternative, namely theft or neighbors begging for a loan. Microsaving is most often used to keep money away from husbands, according to Armendáriz and Morduch. Indeed, microfinance generally is most associated with rural women; they constitute an overwhelming percentage of Grameen’s (and other microbanks’) client base.

By the end of the book, however, it’s not clear that anyone can quantify the value of microfinance programs. Would those who participate in microfinance have done just as well without it? To gauge the actual impact of microfinance, one needs to answer that sort of counterfactual — which is, for obvious reasons, difficult if not impossible. There’s also a problem of what we’re modeling: if we’re trying to quantify, say, small-business growth before and after the introduction of a microfinance program, that’s one thing, and is relatively easy to answer. If we’re trying to measure empowerment of women, that’s quite another, and it’s not at all clear that we even know how to start measuring that. Should we measure it, for instance, by the rate of reported domestic violence? Empowerment may increase reporting rates. It may also cause a shift in the balance of power at home, which may increase violence.

The difficulties are manifest, as Armendáriz and Morduch are well aware. The great virtue of this book is that it doesn’t shy away from pointing out areas of ignorance and future challenges. Anyone interested in how microfinance actually works — and how one would actually measure its success — cannot avoid reading this book.