18 <u>Table 3: Assumptions in estimating returns to nutrition program</u>

|<br>**Parameter**|<br>**Assumption**|<br>**Source**|
|---|---|---|
|_Counterfactual trends:_|||
|Stunting (_S_)<br>|2016 rate from WDI, closest year. Trend before and after<br>follows -1.5% p.a. growth, based on analysis in section II<br>|Authors’ assumption<br>|
|Cognition (_C_)|2016 z-score assumed to be 0.0 SD. No trend assumed|Authors’ assumption|
|Per capita income (_y_)|2016 per capita income from WDI, closest year. Country-<br>specific trend thereafter given by country-specific growth<br>rate from IMF World Economic Outlook forecast, with<br>growth rate being reduced over time according to reciprocal<br>function with 2125 growth rate equal to 50% of 2016 growth<br>rate|Authors’ assumption|
|_Program effects on:_|||
|Stunting �dS��t�dD��t�<br>⁄<br>�|20% reduction (assumed relative to counterfactual).<br>Program assumed to be scaled up over 10-year period, 20%<br>reduction below trend being reached in 2025. Program<br>remains in place thereafter so stunting remains 20% below<br>trend thereafter|Bhutta et al. (2013)|
|Cognition �dC��t�dD��t�<br>⁄<br>�|0.487 extra SDs of cognition relative to counterfactual.<br>Program assumed to be scaled up over 10-year period, 0.487<br>increase above trend being reached in 2025. Program<br>remains in place thereafter so cognition remains 0.487 SDs<br>above trend thereafter|See Table A1. For each intervention in<br>**Error! Reference source not found.**<br>we multiply the estimated cognition<br>effect by 0.9 minus the fraction of<br>children currently covered by the<br>intervention.<br>Current<br>intervention<br>coverage rates from various sources.<sup>8</sup>|
|_Transmission of effects from_<br>_childhood to adulthood_|||
|Stunting|Assume 15 years before joining labor force, and adult|Authors’ assumption|
|�∂S��t�τ�∂S��t��<br>⁄<br>Cognition<br><br>|working life of 40 years||
|�∂C��t�τ�∂C��t��<br>⁄|||
|_Effects of stunting on:_|||
|Education (∂E�/∂ES�)|-1.594 fewer years of education|See Table A1|
|Height (∂H�/∂ES�)<br>|-5.981 cm shorter|See Table A1|
|_Returns to:_|||
|Education (_r_)|Region-specific percentage extra income per extra year of<br>education|Montenegro and Patrinos (2014)|
|Height ()|1.7% extra income per extra cm|See Table A1|
|Cognition ()|4.3% extra income per extra SD|See Table A1|
|_Elasticity of income with_<br>_respect to human capital, i.e._|0.67|Hanushek and Woessmann (2012)|
|_labor share (__)_|||
|<br>_Program costs_|Aggregate costs for WHO groups of countries divided by<br>aggregate population to get per capita costs for each WHO<br>group. Given program assumed to be scaled up over 10-year<br>period, per capita costs also rise accordingly, reaching full<br>per capita cost only in 2025. Cost stays constant thereafter|Bhutta et al. (2013)|
|_Discount rate_|5%|Authors’ assumption|
|_Time horizon_|2125|Authors’assumption|

> 8 The coverage rates for breastfeeding and maternal multiple micronutrient supplementation are the same as those used by Bhutta et al. in the LiST model (Walker et al. 2013). The iodine supplementation coverage indicator is salt iodization; the data are from UNICEF (http://data.unicef.org/nutrition/iodine.html).