Answered myself. lol.
The Kinsey Study into Average Penis Size
Possibly the largest scientific penis size survey to date was conducted by Alfred C. Kinsey in 1948. After gathering measurements from 3500 white college males, Kinsey and his associates concluded that the group's average erect penis length was 6.21 inches and average erect girth measured 4.85 inches. Over 65 percent of the group measured between 5.5 and 6.5 inches in erect length, and it was concluded that falling anywhere within these ranges could be considered 'average'.
In all cases, erect length measurements were taken along the top of the penile shaft, from the pubic bone to the tip of the penis and erect girth was measured around the middle of the shaft.
But like so many studies into penis size, the Kinsey survey suffered from one major drawback - the subjects measured themselves. The college students simply held postcards against their penises, marked off length on the card and posted the results back to the researchers.
There was no independent verification of the measurements taken, and as such it is impossible to know how accurate the measurements used in the study were. In fact, the results of more recent studies into penis size suggest that men tend to exaggerate their penis size when allowed to measure themselves, and this throws into doubt the accuracy of Kinsey's results.
However, Kinsey's study is important because of the sheer volume of participants. The more participants there are within a study, the less the results are effected by extremes. Because of this, men who reported extremely large or small penis measurements in Kinsey's survey did not significantly distort the overall average.
The Kinsey survey is still considered to be one of the most authoritative studies ever conducted into penis size. More recently however, condom manufacturers such as Durex and Lifestyles have also conducted their own research - mainly in an attempt to provide better fitting products.