Propane Usage

[mikeadams50]

I have a 380TH and when camping during rather cold weather low 30's at night mid to high 40's during the day, I would use a 40 lb bottle every 4 days. thermostat set at 68 degrees, from 630pm until 530 am, and 50 degrees during the daytime. Does this seem normal, could not use the Elect heat as I only had a 20amp circuit available to hook up.