The adjustment for temperature is made using number of degree days. The number of degree days is a measure of the heating requirement. It is assumed that heating is not required when the medium temperature during the day and night is higher than 17 °C. The figure for degree days for one day and night is defined as the number of degrees that the medium temperature is below 17 °C. The energy use is adjusted for temperature by adjusting the part of the total energy use that is dependent on temperature. This is done for each building based on the degree days for the particular year for the municipality of the building and the corresponding normal degree days (1961–1990) for that municipality.