According to the statistical data of the literature survey on Normal Male Penis Growth and Development (Fu Chao, Li Xuliang), after the birth of male boys, the development of tintin generally goes through the following four stages.
1. Long-term madness (before the age of 1)
Before the age of one, babies develop very rapidly, including penile development, which can be described as a growth spurt of 8.5%. Maybe you think that’s crazy? Less than 10%. As the saying goes, no contrast, no harm, you keep looking down.
2. Hibernation period (1-10 years old)
After the age of one, the penis seems to enter a long “hibernation period” and develops slowly. Hibernation lasts until you are about 10 years old. During this decade, the average annual growth rate is only 2.65 percent, less than half that before the age of 1, and the highest growth rate is only 4.8 percent. Now you know how great you were before you were 1 year old.
3. Opening period (11-15 years old)
At the age of 11, the penis, which has been dormant for nearly a decade, wakes up and opens, with an average annual growth rate of 11.44 percent and a peak of 14.5 percent. Unfortunately, it only lasts until you’re about 15.
4. Limit period (aged from 16 to over 20)
At the age of 16 or so, the penis begins to show a sign of weakness and the growth rate drops endlessly; by the age of 18, the growth rate drops to 0.96%, almost the limit of decline.
It is also because the annual change of the penis is not obvious after the age of 18, so in the currently searchable literature, the annual data of penis development between the ages of 0 and 18 is very detailed, and the data after the age of 18 is very general.
Nevertheless, the boys do not be discouraged, although the adult penis grows slowly, but not stop the development, accumulate sand into a tower, gather armpit into a mica, a few years down, there will be no small harvest.
The literature “Survey on Normal Penis Growth and Development of Male” (Fu Chao, Li Xulang) included all males over 18 years old, regardless of age, into an adult group. Data showed that the penis size of the adult group was 11.4% larger than that of the 18-year-old group.
In the literature 3d Digital Image Analysis of Adult Penis (Chen Hua, Li Shirong, etc.), adult males were divided into four groups according to age: 18-20 years old group, 21-29 years old group, 30-39 years old group, and 40-50 years old group.
The penises of the 21 – to 29-year-olds were 9.73 percent larger than those of the 18 – to 20-year-olds.
However, there was no significant difference in penis size between the groups of 21~29 years old, 30~39 years old, and 40~50 years old.
As a result, the penis gradually stops developing in your 20s.