How would I minus a number by 1000 instead of reseting it to 2000? [closed]

````So I am trying to make a script that allows the player to minus the number and add the number but there is a minimum number. I have already figured out how to make a limit but when I minus the number it resets to 2000 and when I add the number it goes back to what it was on when I added it.

Add script:

local z = Instance.new("DoubleConstrainedValue",script.Parent)
local vz = script.Parent.Parent.Variable2

z.MinValue = 2000
z.MaxValue = math.huge

function onButtonClicked()
z.Value = z.Value + 1000
vz.Text="z:("..tostring(z.Value)..")"
end

script.Parent.MouseButton1Click:connect(onButtonClicked)

Minus Script:

local z = Instance.new("DoubleConstrainedValue",script.Parent)
local vz = script.Parent.Parent.Variable2

z.MinValue = 2000
z.MaxValue = math.huge

function onButtonClicked()
z.Value = z.Value - 1000
vz.Text="z:("..tostring(z.Value)..")"
end

script.Parent.MouseButton1Click:connect(onButtonClicked)

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