▁In ▁October ▁ 2 0 0 9 , ▁the ▁construction ▁company ▁E ma ar ▁announced ▁that ▁it ▁had ▁completed ▁the ▁exterior ▁of ▁the ▁building ; ▁within ▁two ▁months , ▁the ▁Dub ai ▁government ▁came ▁close ▁to ▁default ing ▁on ▁its ▁lo ans . ▁Stephen ▁Bay ley ▁from ▁The ▁Daily ▁Te legraph ▁commented , ▁" For ▁all ▁the ▁amb ition ▁of ▁its ▁construction , ▁Dub ai ' s ▁new ▁K hal ifa ▁Tower ▁is ▁a ▁fright ening , ▁pur pos eless ▁monument ▁to ▁the ▁sub prime ▁era ". ▁ ▁Emp ir ical ▁test ▁of ▁the ▁Sk ys cra per ▁Index ▁hypothesis ▁A ▁study ▁by ▁Bar r , ▁M iz rach ▁and ▁M und ra ▁( 2 0 1 5 ) ▁a ims ▁to ▁see ▁if ▁there ▁is , ▁in ▁fact , ▁a ▁correlation ▁between ▁sk ys cra per ▁height ▁and ▁economic ▁growth . ▁The ▁study ▁looks ▁at ▁two ▁types ▁of ▁data . ▁First , ▁the ▁paper ▁looks ▁at ▁the ▁announ cement ▁and ▁completion ▁dates ▁of ▁the ▁world ' s ▁tall est ▁buildings ▁and ▁the ▁pe aks ▁and ▁tr ough s ▁of ▁the ▁United ▁States ▁business ▁cycle , ▁as ▁measured ▁by ▁the ▁National ▁Bureau ▁of ▁Econom ic ▁Research . ▁They ▁find ▁that ▁there ▁is ▁virt ually ▁no ▁relationship ▁between ▁the ▁timing ▁of ▁record - bre aking ▁buildings ▁and ▁the ▁business ▁cycle . ▁Second , ▁the ▁authors ▁investigate ▁height ▁and ▁economic ▁growth ▁using ▁the ▁time ▁series ▁techniques ▁of ▁vector ▁autor egr ession ▁and ▁co integration ▁tests . ▁They ▁investigate ▁the ▁time ▁series ▁relationship ▁between ▁the ▁tall