Since the 1930s, the conventional wisdom among economists has held that producer prices are more rigid than consumer prices. The roots of this view lie in the 1930s-era “administered price” thesis, which states that large firms set their prices more rigidly than do small firms. In this post, we report that this old “fact” is not true. We instead find that the prices set by large firms are much more flexible than those set by small firms. A key implication of this finding is that policymakers concerned about inflation or deflation should pay particular attention to changes in large firms’ prices.