In this section, we use an OLS estimator and test for stationarity with a Breusch-Godfrey test. As we found stationarity for most countries we then corrected by instrumenting lags and finally settled for two lags as the minimum requirement to correct for stationarity in all countries. Given the short time-series available, the options of including other variables in the equations or use cohorts fixed effects were not considered.

When the population of working age is taken together (top panel), we only have seven out of 18 countries that show significant coefficients, four U-shape and three inverted U-shape. In age 30-34, only four countries have significant coefficients and only one of these shows a U-shape. In age 40-44, six countries have significant coefficients and half of these are U shapes and in age 50-54 there are three countries with significant coefficients, two of which are U-shapes. There is also no consistency within countries across cohorts indicating that none of the countries has really gone through a U-shape process for any cohorts. A period of 20 years may be too short to observe a full U-shape but these results suggest that there is no law regulating FPRs and GDPs in MENA countries. Only some age groups in some countries have experienced a U-shape process suggesting that this process is country and age specific but cannot be generalized to the population in a country or to the MENA region as a whole. There is not even dominance of U-shapes over inverted U-shapes across countries and cohorts in the MENA region. In fact, we saw in Table 2 that the apparent U-shape shown in Figure 1 for the MENA region is converted into an inverted U-shape by the parametric approach, which suggests a dominance of inverted U-shapes over U- shapes in the region.

**Table 4 – FLP Time-series Regressions by Country and Age Groups (OLS-IV)**

|**Country**|**Age Group**|**FPR_1 **|**FPR_2 **|**lngdp**|**lngdp2 **|**_cons**|**Obs.**|**U/IU**|
|---|---|---|---|---|---|---|---|---|
|UA Emirates|All|1.516***|-0.537**|131.034*|-6.038*|-709.342*|21|IU|
|Bahrain|All|1.538***|-0.564**|640.339|-31.968|-3,205.474|21||
|Djibouti|All|1.075***|-0.071|3.577*|-0.236*|-13.266*|16|IU|
|Algeria|All|1.201***|-0.301|-99.225*|5.748*|429.504*|21|U|
|Egypt|All|0.109|-0.117|-795.669**|47.603**|3,344.721**|21|U|
|Israel|All|1.082***|-0.158|12.166|-0.577|-59.957|21||
|Iraq|All|0.753*|0.186|-7.951**|0.479**|33.980**|11|U|
|Iran|All|1.092***|-0.548**|505.933**|-27.618**|-2,309.045**|21|IU|
|Jordan|All|0.372|0.145|-250.095|15.249|1,031.186|21||
|Kuwait|All|1.210***|-0.324|518.973*|-24.436*|-2,750.168*|16|IU|
|Lebanon|All|1.110***|-0.038|-43.845**|2.266*|210.439**|21|U|
|Morocco|All|0.984***|-0.665***|115.707|-7.235|-443.665|21||
|Oman|All|0.969***|-0.014|63.762|-3.162|-319.738|20||
|Qatar|All|1.094**|-0.204|6,200.865|-278.371|-34,525.647|11||
|Saudi Arabia|All|1.355***|-0.477**|-121.098|6.084|604.606|21||
|Syria|All|1.163***|-0.374|159.427|-10.186|-617.885|19||
|<br>Tunisia|All|1.367***|-0.431*|-18.879|1.091|83.306|21||
|Yemen|All|1.573***|-0.614***|67.618|-4.386|-259.559|21||
|UA Emirates|30-34|1.668***|-0.667***|20.362*|-0.911*|-113.499**|31|IU|
|Bahrain|30-34|1.456***|-0.473**|174.690|-8.907|-855.049|30||
|Djibouti|30-34|1.000***|0.000|0.001|-0.000|0.733***|16||
|<br>Algeria|30-34|1.664***|-0.652***|145.277|-8.329|-633.361|26||
|Egypt|30-34|0.882***|-0.078|-213.160|12.758|895.719|31||
|Israel|30-34|0.556**|0.232|178.128|-8.513|-915.083|26||

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