Just looked at http://www.mormonnewsroom.org/article/mormon-lmissionary-work-worldwide-broadcast

I was just thinking about this. According to the morg, there are now 70,000 missionaries (14,650 girls, 55,350 boys) (I am hoping the 70,000 ignores old couples.) According to the morg, 8 months ago, the numbers were 5,850 and 52,650 respectively if girls made up 10% (this is a reasonable guess since they are making a big deal out of 20% girls today). We can see that the number of mishies increasing over the past 8 months is 11,500.

The expected replacement of the boys over 8 months is 55,350*8/24 (17,500) and for the girls would be 2,850*8/18 (2,600) under the old rules or 2*55,350*8/24 (35,100) for the boys and 3*2,850*8/18 (7,800) for the girls since the cohorts now have an additional 1 year for boys, and 2 years for girls.
(I am making a simplifying assumption that people would leave in the year in which they aged into missionary eligibility)

Well, 35,100+7,800 is 42,900 new mishies. We expected the morg to lose 17,500 + 2,600 (20,150) over 8 months as mishies go home, so the net increase should be 22,750 if people signed up proportionately to previous missionaries

This is much more than the 11,500 that actually occurred

So what happened?

Well, the morg says there are 14,650 girls and 55,350 boys.
Under ideal growth, boys should be at 52,650 + 35,100 – 17,500 or 70,200

Girls would be at 5,850 + 7,800 – 2,600 or 11,050.

Holy crap. That would be 81,250 mishies, but the real numbers are 70,000

Hmmmm. Looks like the girls are signing up way more than expected, and the boys way less than expected.
This is very loosey-goosey, but it does show that 70,000 missionaries, given the easing of ages, is only viewed as a big fat fail for the boys. The participation rate has come way down.

If you extend the analysis to 12 months, the expected numbers are 92,625 total (78,975 boys and 13, 650 girls). We see that this is low for girls, and high for boys.

The morg says at 14 months, they anticipate 85,000 total which means an increase of 11,500 for the first 8 months of the program, and 15,000 over the next 6 months.

Ignore the (admittedly crude) arithmetic if you will, but it does not add up. This is not a success if the metric is “getting a boy on a mission”