Yesterday the Church published an article providing information on the number of young men, young women, and seniors serving full-time missions for October 2012 and September 2013.
The Church currently reports 79,800 full-time missionaries serving worldwide; 21,100 more than a year earlier (36% increase). Young elder missionaries number 54,200 (68%) whereas young sister missionaries total 19,300 (24%). Senior missionaries number 6,300 (8%). In October 2012, there were 58,700 missionaries serving including 44,800 young men (76%), 8,100 young women (14%), and 5,800 seniors (10%).
The percentage increase in young women serving missions is particularly impressive (140%). To contrast, the number of young men serving missions increased by only 21% whereas the percentage of seniors serving missions increased by 8%. Prior to the announcement adjusting the minimum age for missionary service, the percentage of young women comprising the full-time missionary force appeared constant for several years as in 2007 the Church reported that sisters comprised 13% of the worldwide missionary force compared to 14% in 2012.
It is important to note that the Church has also experienced a significant increase in the number of seniors serving full-time missions over the past year (8%) notwithstanding no "age adjustment" or other change in church policy that would explain a sudden increase in this missionary demographic. The Church has recently (2011) made missions more flexible for seniors to accommodate their unique needs and living situations. The implementation of this policy may have contributed to some of the recent increase in the number of senior missionaries serving.
The current number of missionaries serving is less than I originally predicted for the one year anniversary of the adjusted mission age announcement. In an article for cumorah.com, I predicted that there may be as many as 89,000 missionaries serving by October 2013 "due to a net increase of 31,000 missionaries (15,000 missionaries from lowering the mission age for men, 7,500 missionaries from lowering the mission age for women, 5,000 from hypothetically increasing the percentage of single men in North America who serve a mission by five percent, and 3,500 missionaries from the Church perpetuating its six percent annual growth rate for the number of missionaries serving that has occurred over the past two years independent of lowering mission ages)." It appears that the Church has not reached 89,000 missionaries at the one-year anniversary primarily due to a smaller-than-expected increase for young men serving missions worldwide.