If you lost your ATM card on the street, how easy would it be for someone to correctly guess your PIN and proceed to clean out your savings account? Quite easy, according to data scientist Nick Berry, founder of Data Genetics, a Seattle technology consultancy.
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Berry analyzed passwords from previously released and exposed tables and security breaches, filtering the results to just those that were exactly four digits long <0-9>. There are 10,000 possible combinations that the digits 0-9 can be arranged into to form a four-digit code. Berry analyzed those to find which are the least and most predictable. He speculates that, if users select a four-digit password for an online account or other web site, it"s not a stretch to use the same number for their four-digit bank PIN codes.
Somewhat intriguing was #22 on the most common password list: 2580. It seems random, but if you look at a telephone keypad (or ATM keypad), you"ll see those numbers are straight down the middle — yet another sign that we"re uncreative and lazy password makers.
The Least Predictable Password
The least-used PIN is 8068, Berry found, with just 25 occurrences in the 3.4 million set, which equates to 0.000744%. (See the second table for the least popular passwords.) Why this set of numbers? Berry guesses, "It"s not a repeating pattern, it"s not a birthday, it"s not the year Columbus discovered America, it"s not 1776." At a certain point, these numbers at the bottom of the list are all kind of "the lowest of the low, they"re all noise," he says.
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A few other interesting tidbits from Berry:
-The most popular PIN code (1234) is used more than the lowest 4,200 codes combined. - People have even less imagination in choosing five-digit passwords — 28% use 12345. - The fourth most popular seven-digit password is 8675309, inspired by the Tommy Tutone song. -People love using couplets for their PINs: 4545, 1313, etc. And for some reason, they don"t like using pairs of numbers that have larger numerical gaps between them. Combinations like 45 and 67 occur much more frequently than 29 and 37. - The 17th most common 10-digit password is 3141592654 (for those of you who are not math nerds, those are the first digits of Pi).