18. A deep‐foundation engineering contractor has bid on a foundation system for a new world headquarters building for a Fortune 500 company. A part of the project consists of installing 311 auger cast piles. The contractor was given bid information for cost‐estimating purposes, which consisted of the estimated depth of each pile; however, actual drill footage of each pile could not be determined exactly until construction was performed. The Excel file Pile Foundation contains the estimates and actual pile lengths after the project was completed. Compute the correlation coefficient between the estimated and actual pile lengths. What does this tell you?