Average time spent on loo in a life time

Greetings from down under! I send my friends a useless fact for the day each day i’m at work, finding interesting tidbits of trivia and answering questions as they are pondered. I’'ve usually had no problems finding the anwsers that the people seek, but a friend has asked me “On average, how long a person spends on the toilet and is it different for men and / or women”.

I have searched long and hard and come up with a number of possible answers for the first part (including 2,500 hours, 1 1/2 years, 3.8 years, 3 years, 6 months) but nothing on the second. Could you in your infinate wisdom be able to clear this one up?

Many Thanks in Advance!

  Jon