Express entry :Query about years of exp calculation

[Gsk1979]

Hello.
I am currently unemployed. As of jan 1 2018 i have 3.4 years of experience.
My question is how are years of exp counted.
If i get my ita on march 11 2018 will my years of exp reduce to 3.2 ??
Also lets say we file e- apr in may 2018 then years of exp will become less than 3 . At this pojnt willcrs score change ??
Will it cause issue in final pr application?