Which explanatory variable has the LEAST signifiant relationship with FARE?

Variables used in this multiple regression model: FARE: response (dependent) variable - average fare price ($) on that route DISTANCE: distance between the two endpoint airports in miles PAX: number of passengers on the route during the period of data collection SWA: whether Southwest Airlines serves that route (Yes) or not (No) VACATION: whether a vacation route (Yes) or not (No); Florida and Las Vegas routes are generally considered vacation routes HI: Herfindahl Index - a measure of market concentration SUMMARY OUTPUT Regression Statistics Multiple R 0.8567 R Square 0.7339 Adjusted R Square 0.7318 Standard Error 39.3716 Observations 638 ANOVA df SS MS F Significance F Regression 5 2701807.711 540361.542 348.5929 5.5794E-179 Residual 632 979676.999 1550.122 Total 637 3681484.709 Coefficients Standard Error t Stat P-value Lower 95% Upper 95% Intercept 86.67589 7.08935 12.2262 5.2751E-31 72.7544 100.5974 DISTANCE 0.07751 0.00269 28.8351 2.4522E-117 0.0722 0.0828 PAX -0.00011 0.00012 -0.9381 0.3485 -0.0004 0.0001 SWA=YES -61.42324 3.54152 -17.3438 2.0809E-55 68.3778 -54.4687 VACATION=YES 52.21338 3.57526 -14.6041 7.8163E-42 59.2342 -45.1926 HI 0.00735 0.00099 7.3950 4.5121E-13 0.0054 0.0093 4