I noticed that something is wrong with my 40m band dipole with stub match. The SWR value is now almost 3.0.
gnuplot> load "gnuplot.txt"
Freq [MHz]=7.026
V1=7.08
V2=3.68
Cursor 1=5e-09
Cursor 2=0.0
vratio=0.519774011299435
phase1 [deg]=12.6468
phase2 [deg]=0.0
abs(gamma)=0.505804557491017
swr=3.04698187795135
cz={16.5995525105867, 5.07690836540991}