Use of thermostats in US domestic air conditioning systemps

Based on information collected through US Energy Information Administration (EIA) for 2015, only 12% of US 118 million households had a central air-conditioning unit that is actually controlled using a programmed thermostat. About one in three households using central air conditioning do not have a programmable thermostat. But even for those households that use central air conditioning and have a programmable thermostat, more than two-thirds of those households control temperatures without actually programming the thermostat.

See also: https://www.eia.gov/todayinenergy/detail.php?id=32112