▁The ▁National ▁Health ▁Inter view ▁Survey ▁( N H IS ) ▁for ▁ 2 0 1 4 - 2 0 1 6 ▁studied ▁ 3 0 , 5 0 2 ▁US ▁children ▁and ▁ad oles c ents ▁and ▁found ▁the ▁weight ed ▁pre val ence ▁of ▁AS D ▁was ▁ 2 . 4 7 % ▁( 2 4 . 7 ▁per ▁ 1 , 0 0 0 ); ▁ 3 . 6 3 % ▁in ▁boys ▁and ▁ 1 . 2 5 % ▁in ▁girls . ▁Ac ross ▁the ▁ 3 - year ▁reporting ▁period , ▁the ▁pre val ence ▁was ▁ 2 . 2 4 % ▁in ▁ 2 0 1 4 , ▁ 2 . 4 1 % ▁in ▁ 2 0 1 5 , ▁and ▁ 2 . 7 6 % ▁in ▁ 2 0 1 6 . ▁ ▁The ▁number ▁of ▁new ▁cases ▁of ▁aut ism ▁spectrum ▁dis order ▁( AS D ) ▁in ▁C au cas ian ▁boys ▁is ▁roughly ▁ 5 0 % ▁higher ▁than ▁found ▁in ▁His pan ic ▁children , ▁and ▁approximately ▁ 3 0 % ▁more ▁likely ▁to ▁occur ▁than ▁in ▁Non - H is pan ic ▁white ▁children ▁in ▁the ▁United ▁States . ▁ ▁A ▁further ▁study ▁in ▁ 2 0 0 6 ▁concluded ▁that ▁the ▁apparent ▁rise ▁in ▁administrative ▁pre val ence ▁was ▁the ▁result ▁of ▁di agnostic ▁substitution , ▁mostly ▁for ▁find ings ▁of ▁mental ▁ret ard ation ▁and ▁learning ▁dis abilities . ▁" Many ▁of ▁the ▁children ▁now ▁being ▁counted