[Humanoid] Health bar?

So I'm making a health bar that should use TweenSize, but I just need the correct numbering to get it correct.

Right now at ~Subbed~ the number only goes between 0 and 1, but it would need to go into a UDim2 size, Help?

Example :

Health           UDim2
100                    1
90                       0.9
80                       0.8
70                       0.7
And so forth...

function GetSize()
    local Health = Humanoid.Health
    local Subbed = tostring(Health/100):sub(0,1)
    local UD = tonumber(Subbed)
    return UDim2.new(UD,0,.92,0)
end

GetSize()