A couple of weeks ago I wrote something on my thoughts about how our local historically yam based food industry was really competing against a global cereals based food industry. The rice and wheat based products, I argued, were slowly replacing yams in our diets.
I thought this was an obvious observation. Rice and wheat based products like bread and meat pies and the like have spread to every nook and cranny. Fifty years ago I doubt that was the case. Although I must admit, using ones personal observations in lieu of actual data is not very smart. The economist gods must have been ashamed of me. Still, I’m pretty confident that my causal observations are not totally wrong.
Turns out data on historical food baskets is relatively hard to find but there is some recent data on what foods make up people’s diets. The NBS has conducted a general household survey three times in the past decade. In 2010, 2012, and 2015. Its a panel survey so they follow the same set of people each time. Part of the survey is focused on what people spend money on and we can use this to understand what kinds of food people eat and how that changes at least through the duration of the survey.
Caveat: that you spend more on something doesn’t mean you eat more of it. Food A might be really cheap and food B really expensive. So you might spend more on Food B even if you only eat it once a week. Still, the data can tell us a thing or two about food choices. So what does it say?
First, the average household now spends more on rice than on yams. A lot more in many states. Only FCT has a higher fraction of spending on yams against rice.
Now, of course, rice isn’t the only cereal in the country. The north has lots of other cereals besides rice. Millet for instance is very popular in various parts. But even in the north rice is now dominant over other cereals.
Also, yams aren’t the only tuber. Cassava is an alternative which we grow a lot of and is a substitute for yams, kind of. What happens when we compare cereals to tubers in general? The effect of cassava shows. Of course cassava is also a relatively new crop in the country but that’s neither here nor there.
Rice is dominant in terms of spending. But what we really care about is the change over time. Is rice getting more or less dominant? Comparing the changes in the fraction spent on rice to the change in the fraction spent on yams, we see a shift towards rice. I look at the change from 2010 to 2012 because we know what has happened to rice prices since 2014. Food prices between 2010 and 2012 were generally not biased against rice or yams.
In case the graph is not clear enough. This is the change in the ratio of rice to yams between 2010 and 2012.
There is an increase in that ratio but not everywhere. Still there are more rice leaners than yam leaners with the nationwide average showing a shift towards rice. What was perhaps most surprising for me is that the change is not only in urban areas. Rural areas are not left behind in the rice craze although not on the same scale.
Finally, one way to observe food basket changes is to look at those who migrate, either from rural areas to urban areas or vice versa. They tend to be at the forefront of change given the opportunity to re-organize their choices when they move. Since the GHS tracks the same people over time we can observe the changes in those who go from rural areas to urban areas and vice versa relative to those who don’t move.
As expected, those people who moved from rural to urban areas show the biggest tilt towards rice but those who move from urban to rural areas also show a bigger tilt than the average. Very interesting.
Does this count as incontrovertible evidence that rice is replacing yams in our diet? No, it does not. For that we would need much longer data given that food choices change very slowly. But it does show that, at least as far as spending is concerned, rice in now king.