highly significantp < 0.0001
( 0.0001 ) 0.38 ( 0.0004 ) − 0.02 ( 0.8372 ) − 0.16 ( 0.0829 ) − 0.31 ( 0.0001 ) ) ( a t − 3 c t − 3 p t − 3 r t − 3 ) The Portmanteau test for cross correlation of residuals, Durbin Watson tests, and the univariate model AR diagnostics were non-significant, while the R-squared for each series was highly significant (ranged from 0.44 to 0.87, p < 0.0001).