How do I make this countdown?

How do I make it count backward and show the text at the same time.

for i= 1,20 do
	wait(1)
	print(i)
script.Parent.Text= i
end

for i= 20, 1 do
    wait(1)
    print(i)
script.Parent.Text= i
end

Reverse it.

**@Duelingwarlord ** but that doesn't work.