The communication products with highest expenditure shares by households in 2014 were cell phones monthly plans, Internet, cards for the cell phone, and local private lines (Table 1). Threequarters of the total expenditures in telecommunication services are related to mobile communication. In this paper, the focus will only be on aggregate mobile telecommunication items, composed of cell phones (monthly plan), cards for cell phones, and cell phones and equipment, making up a combined share of 2.17 percent of total expenditures.

**Table 1. Expenditure shares on communication services**

||**All**|Poor|est||Househ|old inco|me deci|les||R|ichest|
|---|---|---|---|---|---|---|---|---|---|---|---|
|**Category**||1|2|3|4|5|6|7|8|9|10|
|**Total communication**|**2.91**|**2.35**|**2.33**|**2.42**|**2.68**|**2.76**|**3.09**|**3.11**|**3.33**|**3.36**|**2.70**|
|**Mobile communication**|**2.17**|**1.74**|**1.75**|**1.67**|**1.87**|**1.93**|**2.24**|**2.22**|**2.44**|**2.47**|**2.13**|
|_Cell phones (monthly plan)_|_1.09_|_0.28_|_0.27_|_0.40_|_0.49_|_0.54_|_0.72_|_0.81_|_1.05_|_1.27_|_1.45_|
|_Card for cell phone_|_0.88_|_1.26_|_1.34_|_1.17_|_1.20_|_1.26_|_1.22_|_1.22_|_1.17_|_1.02_|_0.46_|
|_Cell phones and equipment_|_0.20_|_0.20_|_0.14_|_0.11_|_0.18_|_0.14_|_0.31_|_0.19_|_0.22_|_0.18_|_0.22_|
|**Remainder items**|**0.73**|**0.61**|**0.58**|**0.75**|**0.81**|**0.82**|**0.84**|**0.90**|**0.89**|**0.89**|**0.57**|
|_Local calls (private line)_|_0.39_|_0.20_|_0.28_|_0.41_|_0.46_|_0.46_|_0.45_|_0.51_|_0.49_|_0.48_|_0.30_|
|_Internet_|_0.24_|_0.07_|_0.10_|_0.13_|_0.17_|_0.22_|_0.23_|_0.25_|_0.29_|_0.31_|_0.23_|
|_Long distances (private line)_|_0.04_|_0.04_|_0.04_|_0.04_|_0.05_|_0.06_|_0.07_|_0.06_|_0.04_|_0.04_|_0.03_|
|_Public internet, public phone_|_0.04_|_0.21_|_0.13_|_0.11_|_0.11_|_0.07_|_0.08_|_0.05_|_0.03_|_0.02_|_0.01_|
|_Install. of private line phone_|_0.01_|_0.03_|_0.00_|_0.03_|_0.01_|_0.01_|_0.01_|_0.01_|_0.01_|_0.02_|_0.01_|
|_Publicphone_|_0.01_|_0.05_|_0.03_|_0.03_|_0.01_|_0.02_|_0.01_|_0.01_|_0.03_|_0.01_|_0.00_|

_Source:_ World Bank estimates using ENIGH 2014. _Note_ : Deciles based on household expenditure per capita.

# **4.2. The market of corn products**

Competition in the food and agriculture markets is a key component in determining food security in developing economies. Market concentration in the food production chain has been growing, driven by retail chains, raising concerns of higher commodity prices for consumers (McCorriston 2016). Mexico is no exception to this trend, with high market concentration among key food items such as corn grains. In 2014, the four largest firms amassed 31.2 percent of total gross production per INEGI’s economic census. A closer look at corn flour, an important Mexican dietary staple used to make tortillas, reveals that the firms Gruma and Minsa produced more than 90 percent of corn flour (Zahniser 2004). This concentration resulted in a 26 percent price margin increase due to high market concentration in the tortilla market (Aradillas 2018). Figure 4 shows that Mexico’s maize and maize tortilla consumer price index has been consistently greater than the total consumer price index. Since 2010, both have increased significantly in Mexico, suggesting an increase in the consumer food basket.

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