Chapter 8 Population (in millions) Figure 21 | Coverage of sex- and age-disaggregated data for the population of concern to UNHCR | 2000-2018 70 60 50 40 30 20 10 0 ‘00 ‘01 ‘02 ‘03 Total pop. of concern ‘04 ‘05 ‘06 ‘07 ‘08 Sex-disaggregated data available disaggregated data in many countries where the Office is not involved in primary data collection, with a substantial number of countries not reporting disaggregated data to UNHCR or data only partially covering the populations of concern. Demographic characteristics The availability of disaggregated data varies widely between countries and population groups. In general, the quality of demographic data tends to be highest in countries where UNHCR has an operational role and undertakes registration and primary data collection. In countries where national authorities are responsible for registration and primary data collection, it can be more challenging to obtain sex- and agedisaggregated data, even if such data are collected and there is a high-capacity statistical system. Furthermore, data on some population groups are particularly poor, for example IDPs. In 2018, 131 countries reported at least some sexdisaggregated data. This is a significant decline from previous years, including the 147 countries in 2017. The decline is partially accounted for by more attention being paid to the quality of the estimation 60 ‘09 ‘10 ‘11 ‘12 ‘13 ‘14 ‘15 ‘16 ‘17 ‘18 Age-disaggregated data available of the sex breakdown but also partially due to an increasing reluctance of governments to share data. However, the population covered by sexdisaggregated data has increased from 59 per cent in 2017 to 69 per cent in 2018 [Figure 21]. According to the available data, overall males and females were almost equally represented in the population of concern to UNHCR with 25.4 million men and boys and 25.7 million women and girls.91 Coverage of the population of concern to UNHCR by age was lower than for sex. In 2018, 125 countries reported at least some age-disaggregated data, which covered only 43 per cent of the population of concern. This proportion is about the same as the previous year when, as for sex disaggregation, a higher number of countries (136) reported data. Out of the 31.5 million people for whom agedisaggregated data are available, 16.3 million (52 per cent) were children under the age of 18, almost the same as in 2017. The best coverage of disaggregated data was among refugees and asylum-seekers. For refugees, sex-disaggregated data was available for 17.6 million 91 The population of concern to UNHCR includes refugees, IDPs, returnees, others of concern, and stateless people. unhcr > Global trends 2018