Titanium is a high-strength transition metal extracted from its ore via the Kroll process. In the final stage of this process, titanium(IV) chloride, ${TiCl}_4$, is reduced by magnesium metal at high temperatures:

$${TiCl}_4+2Mg\to Ti+2{MgCl}_2$$

What is the percentage atom economy for the production of titanium in this reaction?

Use the following relative atomic masses ($A_r$): $Ti=47.9$, $Cl=35.5$, $Mg=24.3$.