To gauge how CoRD varies across geographic locations within each country, we calculate CoRD for each of the 25 districts in Sri Lanka, the 40 cities in Pakistan, and the 20 cities in Afghanistan for which data are available. We use nominal food prices to demonstrate that CoRD varies across space in each of the countries (see Figure 3). The differences in CoRD can be considerable. In Sri Lanka, the cost of a recommended diet is SL Rs 150 in Jaffna while it exceeds SL Rs 215 in Kalutara, Colombo, and Gampaha districts. In Pakistan, the cost of a recommended diet is less than Prs 70 in Dera Ismail Khan, Dera Ghazi Khan, and Sahiwal divisions, while it is more than Prs 90 in Rawalpindi, Makran, and Islamabad divisions. In Afghanistan, the cost is lowest in Jowizjan (Af 39) and highest in Kabul (Af 48) and Badakshan (Af 49).

Note that CoRD is a calculation of the _cost_ of nutritious diets. This is not exactly a measure of the _affordability_ of nutritious diets in each province or division. Such a measure would entail looking at incomes alongside the cost of nutritious diets. Nonetheless, our initial calculations demonstrate that the cost of nutritious diets, based on nominal food prices, varies within a country.

We look a little more closely into which food groups drive the variability in CoRD across different geographic locations. We calculate the variance in cost across cities for each of the food groups that comprise CoRD (see Figure 4). We find that in Sri Lanka the variances in the cost of the recommended intake of dairy, vegetables, and oils are much larger than those in the cost of starchy staples, a variance of over five to six times more. Quite similarly, in Pakistan and Afghanistan variance of the cost for dairy and vegetables are also higher than for other food groups, about double the variance of starchy staples in Pakistan, for example. Combined with the fact that the share of dairy and vegetables to CoRD is large in each of these countries (i.e., over 50 percent of CoRD for Sri Lanka), we deduce that much of the variability in CoRD across districts or cities is driven by differing dairy and vegetable prices. This is consistent with the idea that such highly perishable products are difficult and costly to transport.<sup>23</sup> Across countries, the variance in protein food prices is relatively low. This could be driven by easy tradability of non-animal sources of proteins (i.e., legumes).

Across countries, some differences in relative variances exist. Only Sri Lanka registers a relatively high variance in oils and fat costs across districts; this could be because missing units for some of the fats in the Sri Lanka food list reduced the types of fat the model could select for this analysis, with some of the missing units comprising cheaper sources of fat. In Afghanistan, the variance in the cost of starchy staples across cities is relatively high, indicating that markets for cereals are less integrated.

- 4.2 The increasing and seasonal cost of nutritious food

To understand how the cost of nutritious foods has changed over time, we calculate the NPI for Sri Lanka, Pakistan, Afghanistan, and India. We use monthly data for Sri Lanka from January 2013 to December 2017, for Pakistan from July 2008 to June 2017, for Afghanistan from March

> 23 The price of dark green leafy vegetables in Pakistan is unavailable for the city-based calculations. As such, these vegetables are excluded from the city-based CoRD calculations.

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