The question behind a new study by CGAP, the World Bank based Consultative Group to Assist the Poor, is “are mobile phone customers likely to send money to the same people they call?” It sounds a plausible theory, and one that would help with the growth of mobile money transfers.

CGAP analysed data from calls and mobile money transactions performed by over 10 million MTN customers across Cote d’Ivoire, Rwanda and Zambia during a seven month period in 2013. Whilst the majority of voice calls were short distances of under 100km (76 per cent of calls), the majority of mobile money transfers were over 100km (67 per cent). They concluded that – so long as long distance voice calls were used, and not short local ones – then there is indeed a correlation.

“In order to predict a high-use area for mobile money, providers might be better off filtering their analysis to focus on calls that are over longer distances,” said Michel Hanouch, of the Technology and Business Model Innovation Team at CGAP. Mobile money providers cannot automatically assume that all identified voice corridors will be popular for transactions.

“These longer distance calls should be helpful in identifying a meaningful proportion of the main mobile money corridors,” he added. “For example, if you look at MTN in Cote d’Ivoire, Rwanda, and Zambia, 45-60 per cent of the top long distance voice corridors are also top mobile money corridors.”

Over 95 per cent of the top 200 MM corridors involve money sent from the country’s economic capital, which is the source of 50 per cent of all transactions in terms of volume and value.

75 per cent of towns outside the economic capital are net receivers of funds (the destination of the ‘send money home’ model), which mostly get cashed out. However, a lack of local agents in these areas means that often there is no physical cash available for the recipient of a transfer. CGAP suggests that if providers focus on improve their agent networks, then this will lead to a better overall user experience, and therefore a growth in transactions.

The research gave rise to several unanswered questions. For example, why aren’t some popular voice corridors not also leading mobile money corridors? Is it a lack of demand from customers or a lack of investment on the part of providers?

“We hoped this correlation would be stronger, which would have given mobile money providers (with access to voice data) even clearer direction on where to focus investment in agents, marketing and education campaigns,.” Said Hanouch. “However we still think that voice corridors are useful for providers, and can be used as part of a broader strategy to predict the top mobile money corridors, particularly for those MNOs launching new services.”