So what accounts for HK's 2.5:1 connections:person ratio? Carrying multiple phones? Phone plus laptop/watch/ipad?

Edit: or maybe multiple sims per phone

Also people buying Hong Kong sims for access to uncensored internet by roaming in Mainland China.

In many countries people carry more than one phone/SIM card. Mostly for separation of concerns, i.e business and pleasure.

Also for tariffs across providers. It isn't unusual to have one carrier better for data and another for voice/sms.

Another significant factor is contacts. If your contacts are on one network and you are on another, there is enough motivation to get a second device as intra-network is cheaper than cross-network

Also, an extra SIM card is a useful option in case one network goes down.

Wouldn't a mobile number, a home number and Skype number count?

I wondered if perhaps some of these are also business numbers? Unless they were excluded?

It would be interesting to know what prevalence of dual-sim phones are in those countries. Equally tourist levels as there appears to be no single definition of active phone numbers per country. Do they include roaming numbers, some may, some may not. But no single source for this data set and each number set has its own source for that data, which have no standard metric across all sources for how they are measured.

But certainly a more insightful way of viewing this data than the totals alone.

It is, but the comparison cannot be done, since the numbers vary from 2013 (2009 according to another top comment) and 2019.

The percentage would be cool to compare across countries, but sadly it is not possible with this data.

I'm not surprised by Hong Kong, but why are Canada and Australia so low?

Also Maldives at #2. Population: 392,473 [1].

[1] https://en.wikipedia.org/wiki/Maldives