Received: 3 October 2018
Accepted: 27 May 2019
First Online: 19 July 2019
Ethics approval and consent to participate
: No ethical clearance was required since the data used in the study is secondary and available in the public domain. No prior consent was needed. More details regarding the ethical standards maintained during the collection of Census data is available at ExternalRef removed.
: Not applicable.
: The authors declare that they have no conflict of interest.