World map of prevalence rates of female genital mutilation (FGM) by country, as far as can be determined as of May 2020. 
  90–98%
  80–90%
  70–80%
  50–70%
  30–50%
  15–30%
  5–15%
  1–5%
  Determined or estimated below 1%, or unknown
  No data
Own work, derived from File:Composite FGM world map.svg (August 2018), which was primarily based on the 2016 UNICEF report. 
Unless otherwise stated below, all data are based on Female genital mutilation/cutting: a call for a global response. End FGM European Network, U.S. End FGM/C Network and Equality Now (March 2020). Retrieved on 6 May 2020. This shall be referred to as "the Global Response report" or "the March 2020 report" for short. 
The Global Response report notes that the quality of data varies widely from country to country; it has grouped countries in four categories according to the reliabilty of the evidence for prevalence rates of FGM per country (from strongest evidence (category 1) to weakest evidence (category 4):

Category 1: countries with available data on FGM/C from nationally representative surveys (32 in total).
Category 2: countries with available data on FGM/C from indirect estimates (31 in total).
Category 3: countries with available data on FGM/C from small-scale research studies (15 in total).
Category 4: countries with available data on FGM/C from media reports and anecdotal evidence (14 in total).Some assumptions made to interpret the data will be inaccurate, more so as the available evidence becomes weaker and more scarce. 
The colour beige (specifically, FFEEAA) is used to indicate either that FGM rate in a given country has been determined to be below 1%, is estimated to be below 1% (e.g. based on the fact that it has only been observed in a single or few small ethnic groups that comprise less than 1% of the country's population), or where the prevalence rate is unknown even though FGM has been demonstrated to occur in that country (this includes countries like Brunei where prevalence is thought to be very high (due to religious and political factors) and countries like Colombia where prevalence is thought to be very low (due to ethnic demographic factors)). This separates these countries from countries without any data at all (grey).

IndonesiaThe large 2016 UNICEF study found a prevalence of 49% amongst girls aged 0 to 14. The Global Response report (p. 21, 48) notes a prevalence of 49.2% amongst girls aged 0 to 11, apparently based on the same 2016 UNICEF report. However, many girls/women undergo FGM at a later age, for which UNICEF had no data. Smaller recent studies have found prevalence rates of 70–92%, which is likely closer to the total figure. Even if it is to be assumed that the lower percentage amongst the younger generations indicates that the practice is in decline, the prevalence amongst the older generations has probably not yet been replaced. Moreover, researchers fear FGM is actually on the rise since 2010 after endorsement by the Ulama Council and apparent endorsement by the Ministry of Health. Indonesia is therefore provisionally represented as '70–80%'.

PeruThere is anecdotal evidence of FGM (namely, clitoral subincision) amongst the Shipibo population of Peru, with claims that the Conibo and Amahuaca tribes also practice it, though there are no known prevalence rates. Even if all these tribes had a 100% prevalence rate, however, this would still be far below 1% of the total population of Peru of over 32 million (2020).

Fielder &amp; King (2004)       Sexual Paradox: Complementarity, Reproductive Conflict and Human Emergence, p. 170–171 Retrieved on 6 May 2020. ISBN:  9781411655324. 
(2010)  Atlas of Gender and Development How Social Norms Affect Gender Equality in non-OECD Countries: How Social Norms Affect Gender Equality in non-OECD Countries, OECD, p. 129 Retrieved on 5 May 2020. ISBN:  9789264077478. 
John Chua (29 June 2017). "London Doctor exposes global FGM scandal". The Independent. Retrieved on 5 May 2020.
John Chua (5 October 2017). "FGM: A native affliction on every inhabitable continent". Aljazeera. Retrieved on 5 May 2020.
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