The STEP survey includes background information of respondents including demographic characteristics, education, employment history, and earnings. It also includes a reading literacy assessment, administered along with the household survey to a representative sample of urban adults aged 15‐64 in participating countries. Respondents were asked to take a paper‐based literacy test that was designed to measure the level of proficiency in literacy with respect to word meaning, sentence processing and basic passage comprehension, in the language of their resident country. Scores were given based on accuracy (the number of correct answers) and rate (the time taken to answer correctly) on a scale from 0 to 500, as in the PIAAC (Pierre et al. 2014).<sup>10</sup> For analytical purposes, we standardize scores to have a mean of zero and a within‐country standard deviation of one in country‐specific analyses and standardize scores across countries when analyzing the pooled sample, following Hanushek et al. (2015) and Valerio, Sánchez Puerta, et al. (2016b).<sup>11</sup> There is a consistent sampling strategy (see Pierre et al. (2014)) across all STEP participant countries and this paper employs the sample weights within each country in the estimation. Pooled analyses give each country the same weight.

In both our descriptive learning trajectory model and the linear regression model, we limit the estimation sample to survey respondents who have 1‐12 years of schooling. This gives us sample sizes ranging from 1,558 in Bolivia to 2,503 in Vietnam, as Table 1 Panel A shows. The average age of the pooled sample across 5 countries is 32.9 years old, ranging from 28.5 years old in Kenya to 38.1 years old in Vietnam. The average years of schooling is 8.9 years, with about 21.2% still at school. Respondents in Vietnam achieve the highest reading proficiency score (234) while respondents in Ghana have the lowest (126).

For the analysis of labor market returns and the net present value of lifetime earnings, we restrict the sample to adults between 25 and 64 years old who are in the labor force regardless of employment status, since the level of skills matters in both job seeking and job performance. It includes the following groups: (1) the full‐time and part‐time employed (including self‐employed) population, and (2) those who are unemployed but have been looking for jobs in the past four weeks and will be available in the next two weeks. We exclude individuals who are not in the labor force, specifically those who are not employed and did not look for work in the past four weeks, either because they self‐identify as housewives (47.0%), are retired or in old age (24.0%), are ill or disabled (7.9%), are currently attending school (6.1%), do not want to work or believe there are no jobs (3.4%), and for other reasons (11.6%). The earnings measure used is weekly wages in US dollars. The top 1 percent of weekly earners (likely due to reporting error) are excluded from the sample, as were those who did not report their wages (5% of those who report working). The earnings of unemployed people and unpaid workers are set at 0.00001 for estimation purposes.

Table 1 Panel B provides summary statistics of this subsample. The sample size ranges between 1,228 in Bolivia and 1,948 in Kenya, with a total of 8,156 observations in the pooled sample. Vietnam has the highest employment rate at 98.0%, and the lowest rate is 83.1% in Kenya. Hourly wage ranges from $2.8 (PPP 2011) in Ghana to $4.6 in Bolivia. Respondents in Vietnam achieve the highest literacy score (237) and respondents in Ghana the lowest (121). The average years of schooling ranges from 11.1 in Bolivia to 7.8 years in Ghana.

> 10 The STEP survey also collected data on socioemotional skills, but we focus on the measured cognitive skills (i.e., reading proficiency) in the empirical specification, as this is the most consistently measured learning outcome in education impact evaluations. 11 All 10 plausible values of the STEP reading proficiency scores are taken into account using the STEP module in Stata 14 (Macdonald 2014).

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