Do the indexes measure cost differentials between cities?
No. This is one of the more common errors in the application of ENRs indexes, which only measure the trend in an individual city and in the U.S. as a whole. Differentials between cities may reflect differences in labor productivity and building codes. Moreover, quoting bases for lumber and cement vary from one city to another. One city may report list prices while in another prices for the same material may include discounts.
