highchart from curl json datas

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$30 - $250

Project Description:
I'm running one website to based on mysql, php 5.2
One of the menu pages has been showing realtime stats data from Bitcoin market, network through Curl JSON data

1. I need to save the result on a certian file of my server at a desired period like every 5mins or hourly, which no idea how it affect my webserver performance.
2. then convert the result to highchart menu page and update at given times

A reference sample is like this place, http://blockchain.info/charts/market-price
But need to add some optional menu to like daily, week, month, year and visitor's input customized range as well.

I've tried to set highchart.js to test it on my site then no problem at all though just sample data to loaded into script itself.
But I have no idea how PHP can save the json result on certian file then parse out for chart appearance.

I'm not sure whether I've explained all stuffs that u guys may need to understand what I need exactly.
if you need additional infos, just pm me

Additional Project Description:
05/05/2013 at 4:44 KST
I have a CSV datas for old price(block) history and other as well. just need to insert new realtime stats on there. then export out for chart appearance.

Skills required:
AJAX, HTML, MySQL, PHP, Website Design
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