This morning I found an interesting tool on the JDBliss - Balancing Life and the Law site. You input times you arrive at the office and leave the office, and then you input time spend on administrative matters, personal matters, professional development, and meals. It works for working at a law firm or working for yourself. It then calculates how many hours a year (and how many a week) you will need to work at home to meet your target hours. I was stunned by the outcome for my days - no wonder I'm so tired!
Do your own work-life balance and let us know what your results are.