As other commentors have added there is definitely a sex difference in medical mortality. However there is also a huge societal difference if u are male there is a ~70% higher rate of murder as well as the average military is predominantly male. When looking at life span people dieing at the age of ~20 has a significant impact on average mortality. This means that the statistics will be bias towards males having a lesser life span.

This also has an evolution advantage as males are typically bigger and more agressive. This has been hypothesized to be due to the reproduction advantage of keeping woman alive longer than males. Males are much more expendable than woman as one male can reproduce with many females in the time it takes for a female to produce offspring.

This also leaves the question of why do male and female offspring occur at roughly the same rate? This is simply because if the likelihood changes to drastically one way than the sex with less population will be able to pass their genes on more readily making it an advantage to have more of the lesser population. This will eventually even out as it does with most species on earth.