estimates of the short-run gains closing employment gender gaps while keeping the capital stock fixed (not produced in Pennings (2022)).

As the differences between long-run and short-run estimates are often large, we then study the transitional dynamics to 2050 (the medium-term) using the World Bank Long Term Growth Model (LTGM) of Loayza and Pennings (2022). The LTGM also allows for a slow-but-steady pace of increase in female employment rates. As around half of the countries in MENA are resource-rich, we simulate growth paths for these countries using the Natural Resource Extension of the Long Term Growth Model (LTGM-NR) of Loayza et al. (2022). The medium-run economic gains of closing gender employment gaps in this extension tend to be reduced because resource sectors are not in general labor intensive.

Finally, because gender gaps in employment are often larger for the non-college educated, and education levels among women in MENA have been rising rapidly, we calculate the effects of closing gender employment in a model with capital-skill complementarities (CSC) where closing gender gaps in employment rates could generate an additional boost in the accumulation of physical capital. This model also helps us to consider potential distributional effects through changes in the wage rates of unskilled and skilled workers.

In each of the three models—GEGI, LTGM and CSC—we first posit a production function and calibrate the model to a benchmark (MENA countries or the US). We then simulate the effect of closing the _same_ gender gap in employment rates, which makes our estimates comparable across models. In each case, we present the size of the increase in output per person relative to the baseline (in the absence of the policy change). We then study the role of specific assumptions in explaining the magnitude of the effects. To measure employment rates, we use the data on employment-to-population ratios from Pennings (2022), with the share of workers across different levels of schooling from national estimates in ILOSTAT (for those MENA countries where the data is available).

**Results.** We find gains in output per capita from closing gender employment gaps that are large for most countries in MENA, but (i) are very heterogeneous across countries, (ii) are not as large in the short-to-medium term when physical capital is fixed or the speed at which gaps themselves close is incomplete, (iii) are generally smaller with capital-skill complementarities and an unchanged skill distribution, though higher if share of skilled female workers also increases.

Quantitatively, the increase in long-run GDP per capita in MENA from closing gender employment gaps averages 54% using a Cobb-Douglas production function and the GEGI (median 49%), which is very similar to that in the Arab Republic of Egypt (56%), which we use as a typical country. However, the average gains halve in the short-run if capital remains fixed (they also halve in Egypt). Using the long term growth model (LTGM) at 2050, where we incorporate the structure of the economy in our parameter values and model a transition path, gains lie between what we call the short run and the long run values, averaging 31% (median 34%), with Egypt increasing 3