For each spotlight, pressing data gaps and measurement challenges are also highlighted. These supplemental indicators were selected based on an open consultation with civil society organizations and inputs from other international experts (see Box 3.1). Respondents, including international agencies and civil society organizations, submitted suggestions for additional indicators, along with information on their relevance and, where possible, data sources and how often the data are produced. The recommendations included, for instance, monitoring the "average weekly time spent by women and girls on water collection" for Goal 6 and the "share of women aged 15-49 whose BMI [body mass index] is less than 18.5 (underweight)" for Goal 2.