There was a world population of 6,865,942,377 as of September 1, 2010. The increase in the number of births minus deaths this year was an increase of approximately 80,657,700. Since there is a difference of 331,882,011 people living in the time frame of your birth years, then there should be a 4 year difference in age between the two of you (Steve and St. Mary). Is that correct?
There are 220,980 more births than deaths every day.