The two plots lined up here represent spending and spending corrected for inflation or real volume growth in the top plot versus construction inflation in the bottom plot. On the Inflation plot, the black line represents final selling price, actual inflation. The red line represents the ENR Building Cost Index which is a fixed market basket of labor and materials, not a complete selling price index. All plots are for nonresidential buildings only.
The index shows how cost inflation climbs in periods when spending is accelerating and the index slows when spending is increasing slowly. Also we can see that the major decline in spending resulted in a major deflation in the index. Note the ENR BCI does not show the major decline in the inflation index. That’s because the ENR BCI is not final selling price. It shows what the cost of labor and materials did during that period, but does not capture how contractors adjusted their margins down so deeply due to loss of volume.
The takeaway from this comparison is this:
- Labor and material indices do not show what real total inflation is doing
- When spending increases rapidly, inflation increases rapidly
- When spending increases slowly, inflation increases slowly
- An understanding of which direction and how much spending is moving is more important to predicting inflation than the change in the cost of labor and materials