[cyba]

A lot of y'all are full of shit.

Really? How would you know that?
Oh, of course. Wikipedia, where - incidentally - info can be added to any item by anyone who is registered.
Let's have a look. Three major 'scientific' studies measuring erections. Sample group sizes - 80, 50 and (the Lifestyle Condoms survey - we do want them to fit comfortably), 400 uni students at Cancun, Mexico. 300 got hard. All up :D, 430 guys. Wow, that's got to be definitive. Ignore the graphs..dressing.
Note, Wikipedia also says,

A penis must be completely erect in order to obtain an accurate measurement ..(and, importantly) this may be difficult to achieve in a clinical setting.

I suggest you look at the references in detail. Barely any are about scientific measurement and virtually none that seem to be carry scientific weight. Here's an example,

Human Sexuality Forum "The average erect penis size of American men is 5 inches"

There are only 2 scientifically based studies regarding average penis size in existence. One is a study involving all American men, mostly Caucasian, which was published in the American Journal of Urology in 1996. In this study, the penises were actually measured by urologists, and the avg. erect penis size among American men was determined to be 12.9 cm or 5.0 inches.

The 2nd study is the only scientifically based international comparative penis size study in existence. It's described as the most widespread study of its kind. The Andromedical Study was headed by renown European urologist, Dr. Gomez de Diego of Spain. In this study, Dr. de Diego collected scientific data from an international team of reputable physicians to determine the avg. penis size for the 15 nations involved.

In existence! What a vague, pretentious, unknowledgeable load of nonsense. Gomez Deigo, for instance, simply gathered stats from where-ever he could find them, mainly Urologists (who seem to have more to do with guys' cocks than most other doctors - dont forget the 'clinical setting' statement - except, possibly, venereologists.) His 'data' places Koreans at 6.1", just behind the top-rated Frenchmen at 6.2". Japanese guys come in at 5.1" - ahead of Americans at 5.0", Brazilian males at 4.8", and Saudis at 4.9". Bollocks!
Deigo admitted that the results were not exhaustive (well, knock me down with a feather duster and call me 'a ladyboy's fudge puppy') and stated

"We couldn't find references for many countries and in some cases we couldn't even find the appropriate people to talk to about it."

As for your own statement

93% of guys were under 7".

- it's meaningless. Were they 6.8", 5", 3.4" or 2", or somewhere/anywhere in between?

Get yourself a tape measure, a notebook, and a pen, get in your car, take your credit card (food, petrol, etc.) and go calling on glory holes, saunas, and wherever else guys willingly flop their dicks across the breadth and width of the States. You'll be away for months. See what figures you come up with.*

Then you can measure mine

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* Some wit might say, 'The survey will be biased. A disproportionate number of guys with big cocks ('show-offs') go to saunas and use glory holes, etc.'
Maybe.