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D. GLOBAL SECURITY STRESS vs DEMOCRATIC DECLINE
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World military burden (% world GDP): 2000=2.19, 2014=2.24, 2024=nan
corr(world mil burden, annual change in FreeScore), 2006-2024: +0.12  (negative => more security stress, faster decline)
  2006-2012: mean mil burden 2.42% | mean annual FreeScore change -0.22/yr
  2013-2018: mean mil burden 2.21% | mean annual FreeScore change -0.27/yr
  2019-2024: mean mil burden 2.24% | mean annual FreeScore change -0.46/yr

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E. WITHIN-COUNTRY: MILITARY/SECURITY BURDEN -> DEMOCRACY (2-way FE)
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[E1 level] DV=FreeScore N=4949 entities=161 withinR2=0.001
    milex_l1       -0.2611 (se 0.2282, p 0.253)
    gdp_growth_l1  +0.1033 (se 0.0455, p 0.0233)**
    log_gdppc      -0.3390 (se 2.1814, p 0.876)
    log_pop        -3.6481 (se 3.9169, p 0.352)

[E2 V-Dem] DV=libdem N=4870 entities=159 withinR2=0.023
    milex_l1       -0.0934 (se 0.1324, p 0.481)
    gdp_growth_l1  -0.0083 (se 0.0347, p 0.81)
    log_gdppc      +0.3839 (se 1.5398, p 0.803)
    log_pop        +3.1667 (se 3.1712, p 0.318)

[E3 change] DV=dFree N=4873 entities=161 withinR2=0.009
    d_milex        -0.1569 (se 0.0686, p 0.0222)**
    gdp_growth_l1  -0.0005 (se 0.0250, p 0.984)
    log_gdppc      -0.8129 (se 0.3903, p 0.0373)**

[E4 2013+ era] DV=FreeScore N=1793: milex_l1 -0.4948 (p 0.000286)