Yesterday I decided to turn off the water heater (the only active natural-gas using appliance in the house) and see if the gas meter would register any gas use over the next 24 hours. At the end of this time period, the "half foot" dial had moved approximately 10 degrees. By my calculations, this would be about 0.014 of a cubic ft of gas. Is this enough to necessitate doing a leak test on the pipe system or can this be attributed to temperature fluctuations, etc? (the meter is outside and exposed to sunlight part of the day)