CHICAGO — McDonald’s has another reason to work on bringing people back to its restaurants: energy efficiency.

The restaurant giant released its sustainability update Thursday. The report highlights some of the progress it has made, such as serving more fruit, and increasing its use of fiber-based packaging and sustainably sourced coffee. The findings also touched on two areas where the company said it did not make any progress in 2014.

McDonald’s restaurants in some of its top markets didn’t meet expectations for improved energy efficiency.

Part of McDonald’s energy efficiency problem was that there were fewer customers. McDonald’s tracks its energy efficiency, in part, by measuring kilowatt-hour per guest, or the energy used over the number of transactions for the year. The company looks at direct energy use, such as the use of natural gas, propane, fuel oil and liquified petroleum gas, as well as indirect energy, which reflects the use of electricity.

Though fewer customers visited, which has been tracked through a prolonged sales slump, the restaurants still need to use energy for things such as lighting and machinery. McDonald’s said energy efficiency decreased about 6 percent last year. The company said it has been working on reducing energy use and better managing energy efforts at its restaurants. The company said it would evaluate ways to track its progress in energy efficiency at the restaurants “more holistically.”