Sorting a table of functions by index, but how?

I would like to make a table of functions. Functions have their indexes represented as a level id (e.g. 100, 101, 200, 201, 202...) to change some level properties (lighting, gravity ect) So here is an example:

local functionsTable = {}

functionsTable[100] = function()
	print("This is a function number 100")
end

functionsTable[101] = function()
	print("This is a function number 101")
end

functionsTable[201] = function()
	print("This is a function number 201")
end

You might ask, what's the problem? And a problem comes whenever a player connects to a server, and to apply all property changes in the past, my client script loops trough all of the functions in a table until it reaches current player's level. For example:

local functionsTable = {}
local plrLevelId = 200

functionsTable[100] = function()
	print("This is a function number 100")
end

functionsTable[101] = function()
	print("This is a function number 101")
end

functionsTable[201] = function()
	print("This is a function number 201")
end

for i, v in pairs(functionsTable) do
	print("Index " .. tostring(i))
	if i <= plrLevelId then
		functionsTable[i]() -- calling a function of previous levels to apply changes
	else
		print("Skipped " .. tostring(i) .. " - done")
		break -- all functions of the previous and current level have been applied
	end
end

--[[
Output:
	Index 101
	This is a function number 101
	Index 201
	Skipped 201 - done

Expected output:
	Index 100
	This is a function number 100
	Index 101
	This is a function number 101
	Index 201
	Skipped 201 - done
]]

Not only it skips a function that supposed to called in the order, but it called a function number 101, while function number 100 should be called first. What magic is this? How to go through all functions in a correct order that I assigned by index? Thank you in advance