The Institute for Supply Management’s manufacturing PMI index shows that the manufacturing recovery is gaining steam. The closely-watched index reports manufacturing rebounding in December from 53.6 to 55.9 — its highest level since April 2006. Still, the upturn in activity last month did not extend to all of manufacturing. In fact, only nine of the 18 manufacturing industries reported growth. So, while the headline number is encouraging, only half of the industries grew in December, signaling that the manufacturing recovery is not yet broad-based. As the report notes, serious challenges remain including tight capital that continues to restrict investment and growth. With the manufacturing recovery still trying to find solid footing, policy makers in Washington D.C. should be wary of placing any additional costly burdens on employers.