1 Literacy rate, adult female (% of females ages 15 and above) 2  Literacy rate, adult male (% of males ages 15 and above) 3  Literacy rate, youth female (% of females ages 15-24)  Literacy rate, youth male (% of males ages 15-24)
Asphalt shingles- 30 yrs. (only about 15 yrs. of life, though). Tin- 50-100 yrs. You do the math. Tin is way more expensive, but usually works out to save you over the life of the roof (longer than yours). For Canadian weather, I'd strongly recommend the tin as it sheds snow/rain better. Oh, I'm thinking NW Canada, not sure where you live, but still, tin is the better material all the way around.
The story isn't much different for a gas stove. According to Home Energy Magazine, gas stoves are only 40% efficient compared to a microwave's 55%. But the gas stove is usually cheaper to run because gas is usually a lot cheaper than electricity. The microwave uses less energy, but the gas stove is cheaper financially. Though again, we're splitting hairs, because we're talking about pennies of difference a year.