Apostle Brigham Young read from a report furnished by Elder Geo. Reynolds, as follows: the number of converts (adult) made by the 1900 elders in the field in 1899 was 4100, or a fraction over 2 converts to an elder. The cost of keeping the elders in the field—including transportation, cost of living, and value of time, amounted to $950,000 per annum, or in other words, the cost of making each convert was $250.
This idea was brought out in the discussion that followed, namely, that while the expense of converting the people of the world was great, it should be remembered that much good comes to our young men who take missions, for in this way many of them obtain a testimony of the truth of the gospel. Notwithstanding this and other considerations, it was thought by some of the brethren that the missionary work was being overdone.
[Stan Larson (editor), A Ministry of Meetings: The Apostolic diaries of Rudger Clawson, Signature Books in association with Smith Research Associates, Salt Lake City, 1993, http://bit.ly/rudgerclawson]