Not only is it erect, but it is also bone-pressed, meaning they push the ruler into the pubic bone to get the additional length of the penis that is hidden by a layer of fat in some men. I'll post you some of the studies below:
-2015 study by Brazilian Journal of Urology with over 15,000 people, which to my knowledge is the largest and most comprehensive penis size study using scientific testing methods (not self reporting) ever done, which combined the results of previous studies from all over the world taken over 30 years (worth noting that they found no correlation between penis size and race or nationality): Average is 5.17 inches long by 4.59 inches around. Here is the graph for that study in centimeters (13 centimeters is 5.11 inches):
1996 Journal of Urology study with 80 men: 5.1 inches average erect length
2000 International Journal of Impotence Research study with 50 Caucasian Jewish men: 5.4 inches average erect length (the study was done to help men who were considering getting penis augmentation surgery to increase their size realize that many of them had a normal size already)
2013 Journal of Urology study of 253 Tanzanian men: 5.17 inches average erect length
2007 International Journal of Impotence research study of 301 Indian men: 5.12 inch average erect length
1971 Korean Journal of Urology study of 702 Korean men: 5 inch average erect length
1998 Korean Journal of Urology study of 150 Korean men: 5.28 inch average erect length
2016 Korean Journal of Urology study with 253 Korean men: 5.33 inch average erect length (it is interesting how the average size of the Korean penis increased over the course of more than 40 years by around 0.3 inches, we have noticed similar increases in average height, as well as average breast size in Women though, many believe it is because we are eating more meat with growth hormones in it)
2006 West African Journal of Medicine study with 115 Nigerian men: 5.26 inch average erect length
2019 University College London study with 104 UK men: 5.1 inch average erect length
2020 Journal of Sex and Marital Therapy study which compiled the results of 10 prior studies: Average length was between 5.1 and 5.5 inches.
So with 6 inches you're huge then
"Quagmire, are you the type of guy who takes 'no' for an answer ?"
"My lawyer doesn't allow me to answer that question"
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