Married Couples Greener Than Single Households

This one might be filed under the "no duh" category, but married households (I'd like to add that it would only make since that cohabitating couples would be included in this) use 53% less electricity and 42% less water than when the couple divorces and lives separately. This story (click here) says per capita, one-person households are the biggest consumers of energy, land and household goods, consuming 38% more products, 42% more packaging, and 61% more gas.

Just curious, do you do things around your house in an effort to be more green?