2015
2016
2017
Figure B.4: Expansion of the cell tower network of MPT. The blue dots show locations of
cell phone towers that are added to the data each year, and the black dots show locations
of the pre-existing cell phone towers.
Number of cell phone towers
15000
14350
15000
9941
10000
10000
8836
5000
5000
5
0
MPT
mno1
mno2
mno3
Mobile network operator
5
0
mno4
2009 2011 2012 2013 2014 2015 2016 2017 2018 2019
(a) Number of cell towers by provider
(b) Creation of cell towers over time
Figure B.5: Panel (a) presents the total number of cell phone towers by mobile network
operator. Panel (b) shows when cell towers were reported in the OpenCellID data.
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