▁ 5 4 . 5   percent ▁are ▁between ▁the ▁ages ▁of ▁ 1 5 ▁and ▁ 6 4 . ▁Those ▁aged ▁ 6 5 ▁and ▁older ▁form ▁ 3 ▁percent ▁of ▁the ▁total ▁population . ▁Only ▁two ▁general ▁cens uses , ▁in ▁ 1 9 7 5 ▁and ▁ 1 9 9 3 , ▁have ▁been ▁carried ▁out ▁after ▁independence . ▁The ▁most ▁dens ely ▁populated ▁regions ▁of ▁the ▁island ▁are ▁the ▁eastern ▁high lands ▁and ▁the ▁eastern ▁coast , ▁contrast ing ▁most ▁dram atically ▁with ▁the ▁sp ars ely ▁populated ▁western ▁pla ins . ▁ ▁Eth nic ▁groups ▁ ▁The ▁Mal ag asy ▁eth nic ▁group ▁forms ▁over ▁ 9 0   percent ▁of ▁Mad agas car ' s ▁population ▁and ▁is ▁typically ▁divided ▁into ▁ 1 8 ▁eth nic ▁sub groups . ▁Rec ent ▁DNA ▁research ▁revealed ▁that ▁the ▁gen etic ▁make up ▁of ▁the ▁average ▁Mal ag asy ▁person ▁constit utes ▁an ▁approximately ▁equal ▁bl end ▁of ▁S out heast ▁Asian ▁and ▁East ▁African ▁gen es , ▁although ▁the ▁gen et ics ▁of ▁some ▁communities ▁show ▁a ▁pre domin ance ▁of ▁S out heast ▁Asian ▁or ▁East ▁African ▁orig ins ▁or ▁some ▁Arab , ▁Indian , ▁or ▁European ▁ancest ry . ▁ ▁S out heast ▁Asian ▁features ▁– ▁specifically ▁from ▁the ▁southern ▁part ▁of ▁Bor neo ▁– ▁are ▁most ▁pre domin ant ▁among ▁the ▁Mer ina ▁of ▁the ▁central ▁high lands , ▁who ▁form ▁the ▁largest ▁Mal ag asy ▁eth nic ▁subgroup ▁at ▁approximately ▁ 2 6   percent