I just finished this
EzUTC.com (Ez UpTime Calculator) project. You simply enter either uptime percentage and timeframe or downtime and timeframe — then click "Calculate." Regardless, uptime and downtime are both instantly presented in percentage and days, hours, minutes and seconds format. The results also include bar, column and pie chart output.
Ez UpTime Calculator:
http://ezutc.com/
Please let me know what you think...
Later!