Working Week Completion I work a standard nine to five. Monday through Friday. I take a half hour for lunch from 12:30 to 13:00.

Write me a program which, when run, calculates the percentage of the working week that I have completed at the current moment.

Rules


Only count time actually spent working. I am punctual and do not work
over lunch. 
No input. You may obtain information like current time/date however is convenient. 
The working week is considered complete from end-of-day Friday to midnight between Sunday and Monday.
Timezone is the local timezone. 
Output should be a decimal number, eg 66.25498, percentage symbol optional. 
The program should be reasonably future-proof. It should be able to cope with leap years. 
Output resolution should be a second or better. I like to watch the kettle boil.
Code golf. Shortest code wins.
Python 3, 132

from datetime import*
t=datetime.now().timetuple()
m=max(0,t[3]*2+t[4]/30-18)
print(20*min(5,(t[6]+min(15,m-min(8,max(7,m))+7)/15)))


The resolution is one minute, or 2/45 of a percent. That's more than enough IMO.