Percentage of time spent at home in a lifetime

avg. lifetime: 75 years
days in a year: 365.25
hours in a day: 24
Avg. Total Lifetime in Hours: 75x365.25x24 = y

avg. time spent at home in hours*: 24-8-21 = 14
avg. time spent at home in a lifetime in hours: 14x365.25x75 = x

Percentage of time spent at home in a lifetime: (x/y)x100