(kg). It is then necessary to deal with the measurement issue of converting all these reported units into a single unit, say kilograms.<sup>8</sup> Here, we use a simple price-unit conversion method separately for production and consumption. In terms of production, this method uses the information on prices from households that produce a given item and at the same time sell the same item in different units.<sup>9</sup> We use the median unit price for a given sold item in a given region, residential area, and season to generate household-specific conversion rates. We merge all household-specific conversion rates from all regions, residential areas, and seasons for 2004-05 and 2010-11. Then, we pick the median conversion rate (if there are at least 7 household specific conversion rates) for each item-unit pair (i.e., conversion rates are item-specific). With the resulting conversion rates, items are first converted into the modal unit, and then into kilograms. In terms of consumption, we proceed similarly, using the information on prices from households that consume a given item and also report bought quantities of the same item in different units. Finally, we need to attribute prices to these quantities. To measure both household production and consumption (that includes own produced and gifts that are collected in in-kind units) we use the median consumption prices in a given season-region separately for rural and urban areas, a matter that is discussed in more detail in the next section.

While agricultural production is reported in annual terms through the recollection of the harvest output from the last dry and rainy seasons separately,<sup>10</sup> food consumption is reported with a weekly recall (i.e., seven days before the interview). This introduces an artificial seasonal component to the measurement of consumption that needs to be netted out. Indeed, Malawi, Tanzania, and Uganda have clearly demarcated lean and plenty seasons that largely determine food consumption; that is, seasonality is crucial to understanding consumption behavior. One of the improvements of the ISAs is that data collection is rolled out throughout the entire year. This means that we can remove month effects with two year-month observations. Here, we use

> 8For Tanzania and Uganda unit-conversion rates are not necessary as in Tanzania all quantities are reported in kilograms and in Uganda households provide unit-conversion rates (we use the median for a given region and season). This does not mean that households report in kilograms, but that under several procedures, interviewers transform all units into kilograms.

> 9For more details, see De Magalh ̃aes et al. (2015). There we show that this price-unit conversion method is able to recover more item-unit pairs and has similar precision as the standard market surveys conducted on the field that weighs produce in local markets to obtain physical-unit conversion. This is important because market surveys are costly in monetary terms and are usually not rolled out throughout the year (e.g., the market survey for Malawi in 2014). However, the conversion units might differ across months during the year, as the same crop may have different kilogram weights in two different harvests. All prices are deflated using consumer price indexes (CPI) for food and non food items separately for urban and rural areas — CPI available at the National Statistics Office of Malawi.

> 10This information is stored in separate submodules of the agriculture module. A submodule for a permanent crop season is also provided.

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