Cellphones on the streetThe number of worldwide wireless subscriptions is quickly approaching 75 percent of the Earth’s total population. It’s expected to hit 5 billion this month, according to the market research firm iSuppli.

By the end of the year, global wireless subscriptions are expected to grow by another 100 million to hit 5.1 billion. In addition, the global amount of installed wireless devices will total 4.9 billion by the end of the year, iSuppli says. The difference in numbers accounts for users who purchase extra SIM cards, or subscribe to services for Machine-to-Machine communication systems. iSuppli’s figures include subscriptions for all mobile phones, from basic low-cost handsets to high-end smartphones.

Not surprisingly, iSuppli reports that subscription levels vary wildly depending on region. In Africa and the Middle East, wireless penetration is around 50 percent. In heavily connected Europe, penetration is around 156.7 percent — accounting for the fact that Europeans often have multiple devices and subscriptions.

It would be interesting to see how prepaid cellular phones figure into these numbers. It’s harder to track those devices, but we’ve asked iSuppli to see if they have any prepaid figures for comparison.

To put the wireless numbers in perspective, it’s worth remembering that Earth’s total population only hit 5 billion in 1987. We hit 6 billion in 1999, and today the US Census Bureau clocks total population at 6,869,403,455.

Photo via Ed Yourdon

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