More men or women in this world?

Globally, there are about 105-107 boys born for every 100 girls.
Since 1940, an average of 91,685 more male babies have been born each year in the US than females, a total of 5,776,130 over that 63-year period.
The highest sex birth ratio occurred in 1946 (1,059 male births per 1,000 females) while the lowest occurred in 1991 and again in 2001 (1,046 male births per 1,000 females).
For all available years combined, Chinese (1,074) and Filipino mothers (1,072) had the highest differences between the number of boys born versus girls, while non-Hispanic black (1,031) and American Indian mothers (1,031) had the lowest.

And you know why that is?
My biology teacher told us that it is actually the Y-chromosome in the male sperm cell. Roughly half of the sperm cells are equipped with it, the other half carries a X-chromosome. Those determine if the baby becomes a boy (Y) or a girl (X). The y-chromosome is actually just a X-chromosome with a missing strand, therefore it's lighter and gives the sperm cells equipped with it an advantage in speed. The first cell to hit the egg wins, so y-chromosome carrying sperm cells have a slight advantage. It's marginal but it's there.