Recently the LDS Church Growth Blogspot reported the number of self-identifying LDS according to the 2020 Census in Mexico. Previously I've estimated Mexico to be about 15% active members. The census showed 22.5% of the members self-reporting as LDS.
The Church claims 1,498,296 members. 337,998 people in Mexico identify themselves as Mormon. Stem, who estimates by congregation sizes, has estimated Mexico has about a 15.37% percent activity rate--or 227,750 active members. I'm going to continue to say I'm probably pretty close assuming there may be quite a few members who self-identify but are not active.
From The blogspot:
Overall, the percentage of self-affiliated Latter-day Saints in the population slightly decreased from 0.24% to 0.22% between 2010 and 2020. The 2010 census reported 314,932 Latter-day Saints, whereas the 2020 census reported 337,998 Latter-day Saints. There was a net increase of only 23,066 self-affiliated Latter-day Saints between 2010 and 2020, whereas Church-reported membership increased by 246,985. Thus, the increase in the number of census-reported Latter-day Saints was 9.3% of the Church-reported increase in membership during this time. The Church in Mexico has struggled for decades with low convert retention and member activity rates. Probably only 20% of Church-reported membership in Mexico regularly attends church - a percentage that has not appeared to have significantly changed in the past two decades based on survey data from returned missionaries and local members and census data (i.e., 23.2% of Church-reported membership self-affiliated on the census in 2000). The number of Latter-day Saint congregations in Mexico decreased between 2010 and 2020 from 2,007 to 1,843 primarily due to the consolidation of wards with few active members. Moreover, Latter-day Saints are the most urbanized religious group among the largest religious groups on the Mexican census, and this appears primarily attributed to the centers of strength policy. Two-thirds (65.4%) of self-affiliated Latter-day Saints in 2010 resided in cities of 100,000 or more people—the highest percentage of any other major religious group in Mexico. Only 47.7% of Mexicans lived in such cities at the time. There has also been research that indicates Latter-day Saint families in Mexico have fewer children than non-Latter-day Saint families in Mexico per Fox K (2011) Mormon fertility in Latin America found in the BYU Scholars Archive.