Saving/Loading High Scores

Im trying to save and load high scores in my game. Here is what I have:

ego.lua

[lua]–Save function
function saveFile( fileName, fileData )
–Path for file
local path = system.pathForFile( “highscore.txt”, system.DocumentsDirectory )
–Open the file
local file = io.open( path, “w+” )

–Save specified value to the file
if file then
file:write( fileData )
io.close( file )
end
end

–Load function
function loadFile( fileName )
–Path for file
local path = system.pathForFile( “highscore.txt”, system.DocumentsDirectory )
–Open the file
local file = io.open( path, “r” )

–If the file exists return the data
if file then
local fileData = file:read( “*a” )
io.close( file )
return fileData
–If the file doesn’t exist create it and write it with “empty”
else
file = io.open( path, “w” )
file:write( “empty” )
io.close( file )
return “empty”
end
end[/lua]

And in the game I have:

[lua]ego = require “ego”
saveFile = ego.saveFile
loadFile = ego.loadFile

score = 0

local scoreText = display.newText(score,display.contentCenterX, 150, “Helvetica”, 58)

scoreText:setFillColor(0,0,0)

local function addToScore()

    score = score + 1

    scoreText.text = score

end

highscore = loadFile (“highscore.txt”)

local function checkForFile ()

    if highscore == “empty” then

        highscore = 0

        saveFile(“highscore.txt”, highscore)

    end

end

checkForFile()

local function onSystemEvent ()

    if score > tonumber(highscore) then --We use tonumber as highscore is a string when loaded

    saveFile(“highscore.txt”, score)

    end

end

[/lua]

when I have it display the “high score” it only displays the current score.