3 colored circles for humidity, but don't work fine

hi, i have create a funny face that has 2 circles for temperature
and humidity.
the circles change color depending from values of the 2 things.
the left circle work fine but not the right circle.
the right circle has:
humid 0-20% and 80-100% red circle (very dry and very humid)
humid 20-40% and 60-80% yellow circle (dry and humid)
humid 40-60% green circle (good humidity)

something is wrong about 60-70% of the course of the mouse
and 70-74%.

red circle: $#BLN#<20?100:0$$#BLN#>80?100:0$
yellow circle: $#BLN#>19&&#BLN#<40?100:0$$#BLN#>60&&#BLN#<81?100:0$
green circle: $#BLN#>39&&#BLN#<61?100:0$

of course i have placed BLN instead of WCHN, because when i move the time zone with the mouse
i can see the changes, while WCHN stay freezing at 40.

thank for the help.